me551/geo551 geology of industrial minerals spring 2011
DESCRIPTION
ME551/GEO551 Geology of Industrial Minerals Spring 2011. Commodities, Part 2 Bauxite, Clays, Diamonds, Diatomite, Feldspar, Fluorite, Garnet, Graphite. Reminders. SME discussion Research Projects? (25% grade) Soil/stream sediment survey in Lemitar carbonatites for REE using PXRF - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/1.jpg)
ME551/GEO551 Geology of ME551/GEO551 Geology of Industrial Minerals Industrial Minerals
Spring 2011Spring 2011
Commodities, Part 2
Bauxite, Clays, Diamonds, Diatomite, Feldspar, Fluorite, Garnet, Graphite
![Page 2: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/2.jpg)
RemindersReminders
• SME discussion• Research Projects? (25% grade)
– Soil/stream sediment survey in Lemitar carbonatites for REE using PXRF
– Lesson plans• Any questions on the midterm?
– Due March 22
![Page 3: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/3.jpg)
Bauxite
![Page 4: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/4.jpg)
Bauxite
• Al is 3rd most abundant mineral but never found in it’s native state
• Aluminum ore, most commonly formed in deeply weathered rocks—laterites.
• A common residual or transported constituent of clay deposits in tropical and subtropical regions.
• Composed of a mixture of various aluminium oxides and hydroxides (principally gibbsite (Al(OH)3), boehmite (AlO(OH)), and diaspore (AlO(OH))).
![Page 5: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/5.jpg)
Bauxite
• Bauxite is a product of near-surface alteration of aluminous rocks, creating a zone depleted of Fe and Si and enriched in Al bearing minerals.
• Typical analysis of bauxite:– ~50% Al2O3– ~5% SiO2– 15% Fe2O3– 3% TiO2 (Anatase)
• It is THE raw material for ALL primary aluminum.
![Page 6: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/6.jpg)
Introduction
First discovered by les Baux, France 1821
The first commercial extraction of alumina (Al2O3) from bauxite has been attributed to Henri Sainte-Claire Deville in about 1854
Bauxites: soft/friable, variable textures, colors, sizes
![Page 7: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/7.jpg)
Types
• Not all bauxites are equal
• Can be divided “generally” into• three types:
• – Gibbsitic Al(OH)3 ; Low Temp
• – Boehmitic, >4% AlO(OH) ; Hi Temp
• – Diasporic, >5% AlO(OH) ; Very Hi Temp
![Page 8: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/8.jpg)
What makes a good deposit?
• Proximity to processing plant or infrastructure to export.
• – Low extraction costs
• – Quality:– • High % extractible Al2O3 – • Low % reactive SiO2
![Page 9: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/9.jpg)
Uses
• Blast Furnaces• Iron/Steel Ladles• Electric Arc
furnaces• Tundishes• Soaking Pits• Open Hearth• Cement• Aluminum
Ghana Bauxite Company Ltd- Awaso
![Page 10: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/10.jpg)
Ghana Bauxite Company Ltd- Awaso
MiningMining
• Eighty percent of world bauxite production is from surface minesEighty percent of world bauxite production is from surface mines
• Southern Europe and Hungary, produce from underground Southern Europe and Hungary, produce from underground excavations excavations
• Some surface deposits has no overburden, and on others, the bauxite Some surface deposits has no overburden, and on others, the bauxite may be covered by 70 meters or more of rock and clay may be covered by 70 meters or more of rock and clay
• Deposits that are hardened may require blasting in order to release the Deposits that are hardened may require blasting in order to release the ore ore
• Once the bauxite is loosened into manageable pieces it is generally Once the bauxite is loosened into manageable pieces it is generally loaded into trucks or railroad cars and transported to crushing or loaded into trucks or railroad cars and transported to crushing or washing plants or to stockpiles washing plants or to stockpiles
![Page 11: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/11.jpg)
CBG, GUINEA BAUXITE (ALUMINIUM ORE) MINING OPERATIONS, GUINEAhttp://www.mining-technology.com/projects/cbg/
![Page 12: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/12.jpg)
Production
![Page 13: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/13.jpg)
Production
![Page 14: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/14.jpg)
Bauxite—Geology
• tropical weathering of underlying, aluminium-rich rock
• weathering that forms under conditions of high rainfall, high mean temperature, good drainage, but modest relief and no erosion
• grades in Guinea range 40-60% Al2O3
![Page 15: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/15.jpg)
Geologic Description and Distribution
Geological definition of bauxite
Classification of bauxites, ferrites and transitional rocks. (Schellman 1983).
![Page 16: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/16.jpg)
Minerals common to bauxite deposits
![Page 17: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/17.jpg)
Geologic Description and Distribution
Schematic Bauxite Profile
![Page 18: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/18.jpg)
Geologic Description and Distribution
Bauxite Distribution
•Tropical regions: high T (avg 22°), rainfall (1.2 m);
•SiO2 leached in dry season, Fe2O3, Al2O3 formedduring wet season
![Page 19: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/19.jpg)
Bauxite—Processing
• The first commercial extraction of alumina (Al2O3) from bauxite has been attributed to Henri Sainte-Claire Deville in about 1854.
• Crushing, cleaning/washing and drying
![Page 20: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/20.jpg)
The Bayer Process, which continues to be the most economical method of manufacturing alumina can be schematically summarised in a flow charthttp://chemsrv.uwimona.edu.jm:1104/lectures/bauxite.html
![Page 21: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/21.jpg)
Bayer Process• mining • dissolution of the alumina at elevated
temperatures • addition of flocculants • precipitation of pure Gibbsite • regeneration of the solutions for recycling • heating the Gibbsite to 1100C (calcination)
to give alumina
![Page 22: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/22.jpg)
Bauxite—Substitutes
• Anorthosite
• alunite
• coal wastes
• oil shales
• clay
• silicon carbide
• alumina-zirconia
![Page 23: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/23.jpg)
ClaysClays—Introduction—Introduction
![Page 24: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/24.jpg)
ClaysClays—Introduction—Introduction• Stone age• Types
– ball clay (primarily of kaolinite with illite, chlorite, smectite minerals, quartz)
– bentonite (smectite with feldspars, biotite, quartz)
– common clay (illite and chlorite, others)
– fire clay (kaolinite, halloysite, diaspore)
– fuller’s earth (attapulgite, montmorillonite)
– kaolin
![Page 25: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/25.jpg)
TypesTypes
• layer silicates– layers of tetrahedral and octahedral sheets – Kaolinite, smectite, illite, chlorite, vermiculite– Rich in Al, Si, and water
• the metal oxides and hydroxides and oxy-oxides– gibsite
• amorphous and allophanes– structurally disordered aluminosilicates – Allophane, Imogolite
![Page 26: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/26.jpg)
ClaysClays—definition—definition
• particle size of less than 2 micrometers
• family of minerals
• rock term
![Page 27: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/27.jpg)
Clays—propertiesClays—properties
• chemical composition
• layered structure
• size
• great affinity for water (double in thickness when wet)
• soak up ions, release the ions later when conditions change
![Page 28: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/28.jpg)
Clays—propertiesClays—properties
• When clays become wet, they become plastic• When clays are fired they become hard• Color• plasticity• mineral composition• absorption qualities• firing characteristics• clarification properties
![Page 29: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/29.jpg)
Charge propertiesCharge properties
• Charge development of on silicate clays is mainly due to isomorphous substitution.
• This is the substitution of one element for another in ionic crystals with out change of the structure.
• It takes place during crystallization and is not subject to change afterwards.
• It takes places only between ions differing by less than about 10% to 15% in crystal radii.
• In tetrahedral coordination, Al3+ for Si4+ and in octahedral coordination Mg2+, Fe2+, Fe3+ for Al3+.
• Charges developed as a result of isomorphous substitution are permanent and not pH-dependent.
![Page 30: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/30.jpg)
Charge propertiesCharge properties
• In allophanes, some silicate clays e.g. kaolinite, and the metal oxides the main source of charge are termed pH -dependent charges because these charges depend on the pH of the soil.
• pH depend charges are variable and may either be positive or negative depending on the pH of the soil.
![Page 31: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/31.jpg)
Clay—usesClay—uses• Ceramics
• fillers and extenders
• construction (hydraulic cement, structural clay products, aggregates)
• drilling mud
• fiberglass
• Iron Ore Pelletizing
• paper
• carrier to mix paint and color pigment
![Page 32: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/32.jpg)
Ball clay—usesBall clay—uses
• Burn to a light color and accepts glaze, plastic
• Added to other clays to improve their plasticity
• 35% floor and wall tile• 22% sanitary ware• 43% other uses
![Page 33: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/33.jpg)
Bentonite—uses• Clay consisting of smectites• Formed from alteration of volcanic ash
• Made up mainly of montmorillinite, (Na,Ca)0.33(Al,Mg)2(Si4O10)
(OH)2·nH2O
• Named for Fort Benton, WY, where it was first described as part of a Cretaceous tuff sequence
• 26% pet waste absorbent• 25% foundry sand bond• 19% drilling mud• 15% iron ore pelletizing• 15% other uses
![Page 34: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/34.jpg)
End Use Statistics(USGS 2005)
![Page 35: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/35.jpg)
Properties & Applications
• Thixotropy– Can be semi-solid at rest, but
will be liquid when agitated– Used as a thickening and suspension agent in
paints, dyes, and varnishes
(KSGS 2002)
![Page 36: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/36.jpg)
Properties & Applications
• Absorption / Adsorption– Can absorb several times it dry weight in water– Pet litter, impermeable clay liners, wastewater
treatment, detergent purification, paper pulp purification, de-inking
(IMA-NA 2007)
![Page 37: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/37.jpg)
Bentonite as a Value-Added Commodity
• Bentonite is not often taken straight from the ground to market.
• Much purification is often undergone to specialize the product– Sieving (for granular bentonite)
– Milling (fine and superfine powdered bentonite)
– Removal of associated gangue minerals
– Treated with acids (“bleaching earths”)
– Treated with organics (“organoclays”)
(IMA-NA 2007)
![Page 38: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/38.jpg)
Common clay—usesCommon clay—uses
• 56% brick
• 20% cement
• 16% lightweight aggregate
• 8% other uses (fillers and extenders)
![Page 39: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/39.jpg)
Fire clay—usesFire clay—uses
• Resistant to heat (refractory)
• 73% refractories
• 27% other uses
![Page 40: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/40.jpg)
Fuller’s earth—usesFuller’s earth—uses
• mineral substance characterized by the property of absorbing basic colors and removing them from oils
• fulling of wool to remove oil and grease• Absorbants • Pesticides
• 75% absorbent uses• 25% other uses
![Page 41: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/41.jpg)
Kaolin—usesKaolin—uses
• Near white containing kaolinite
• 55% paper
• 7% refractories
• 38% other uses
![Page 42: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/42.jpg)
Kaolin—usesKaolin—uses
• mildew-resistant latex paints• vinyl wire insulation• printing inks• Cosmetics• rubber tires• fiberglass and nylon• auto and truck body components • production of medicines• ceramics• catalysts for petroleum refining• extenders for fertilizers, pesticides, and herbicides
![Page 43: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/43.jpg)
KaolinKaolin
![Page 44: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/44.jpg)
Clays—substitutionsClays—substitutions
• Limited substitutions possible
• calcium carbonate
• talc
![Page 45: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/45.jpg)
Clays—productionClays—production
– ball clay– common clay: various– fire clay– fuller’s earth: U.S., Germany– kaolin: U.S., Uzbekistan, Czech Republic,
United Kingdom, Brazil
![Page 46: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/46.jpg)
Production Methods
• Drilling & Sampling• Soil Profiling (to aid in
speedy recovery after reclamation)
• Topsoil & Overburden removal (usual with scrapers)
• Quarrying with loader & truck
• Only economic to mine bentonite with no more than 50 feet of overburden
(WMA-Minelife 2007)
![Page 47: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/47.jpg)
Simplified Bentonite Mill Flow-Chart
(WMA Minelife, 2007)
![Page 48: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/48.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 49: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/49.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 50: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/50.jpg)
Clays—geologyClays—geology
• soil horizons• continental and marine sediments
• geothermal fields
• volcanic deposits
• weathering rock formations
• coal beds
![Page 51: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/51.jpg)
Bricks—processingBricks—processing
• Common clay used to make bricks
• formed or shaped either by extrusion– involves forming a column of clay by
pushing the material through a die at high pressure.
– then cut into bricks (known as 'wirecut')– drainage pipes and clay roof tiles made
similar process
![Page 52: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/52.jpg)
Bricks—processingBricks—processing
• or the 'soft-mud' process– individual bricks are formed in a sand-lined
mould from a clay with a relatively high moisture content (known as 'stock' bricks)
– dried prior to firing– fired using natural gas in a linear kiln
known as a 'tunnel kiln’– 1050–1100°C
![Page 53: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/53.jpg)
Environmental considerations—clayEnvironmental considerations—clay
• Open pits
• organic emissions (EPA developing standards, MACT)
• impoundment of slimes
• dust control
![Page 54: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/54.jpg)
Colin C. Harvey, 1999
![Page 55: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/55.jpg)
DiamondsDiamonds
![Page 56: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/56.jpg)
DiamondsDiamonds
• Greek adamas meaning invincible
• Used in India 2,500 yrs ago
• Most popular gemstone
![Page 57: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/57.jpg)
Diamonds—introductionDiamonds—introduction
• clarity, color, shape, size is used to determine industrial-grade diamond (nongem)
http://www.brysonburke.com/diamonds_find_the_source.html
![Page 58: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/58.jpg)
Diamonds—propertiesDiamonds—properties
• Hardest substance known• highest thermal conductivity• chemical stability• optical properties• refract light
atomic connectivity of the carbon atoms gives thegem its hardness
![Page 59: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/59.jpg)
Diamonds—productionDiamonds—production
USGS Commodities SummaryUSGS Commodities Summary
![Page 60: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/60.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 61: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/61.jpg)
Diamonds—usesDiamonds—uses• Middle Ages--healing
powers• Grinding• Drilling • Cutting • Polishing • Abrasives • Wear- and corrosion-
resistant coatings • Special lenses
• Heat sinks in electrical circuits
• Wire drawing• Diamond windows• Heat sinks• Low friction
microbearings• Wear-resistant parts
![Page 62: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/62.jpg)
Diamonds—substitutionsDiamonds—substitutions
• cubic boron nitride
• silicon nitride
• but diamond is more than twice as hard
• synthetic diamonds (US)
![Page 63: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/63.jpg)
Diamonds—geologyDiamonds—geology
• Kimberlites
• lamprorites
• alluvial (placer) deposits for these rocks
• molten rock from 75 to 120 miles below the earth's surface 40 kbar and 900° C
![Page 64: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/64.jpg)
The slightly misshapen octahedral shape of this rough diamond crystal in matrix is typical of the mineral. Its lustrous faces also indicate that this crystal is from a primary deposit
http://en.wikipedia.org/wiki/Diamond
![Page 65: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/65.jpg)
Schematic diagram of a volcanic pipe http://en.wikipedia.org/wiki/Diamond
![Page 66: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/66.jpg)
Indicator mineralsIndicator minerals
• ilmenite
• titanium and magnesium rich chromite
• chrome diopside
• magnesium rich olivine
• pyrope garnets
• eclogitic garnets
![Page 67: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/67.jpg)
CaratCarat
• carat weight measures the mass of a diamond
• One carat is defined as a fifth of a gram
• 200 milligrams
• approximately 0.007 ounce
• point unit—equal to one one-hundredth of a carat (0.01 carat, or 2 mg)
![Page 68: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/68.jpg)
PricePrice
![Page 69: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/69.jpg)
Mining
• Artisanal mining
• Hard rock mining (underground)
• Marine mining
• Open pit or open-cast mining
• Placer mining
![Page 70: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/70.jpg)
MiningMining
Alluvial or artisanal mining by traditional methods continues, as seen here in Sierra Leone.
![Page 71: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/71.jpg)
MiningMining
![Page 72: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/72.jpg)
Diamonds—processingDiamonds—processing
• Crush
• scrubbers and degritting and sanding sections remove fine waste material for disposal
• Heavy-medium separation or grease belts
• X-ray fluorescence sorters are used to extract the diamonds
![Page 73: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/73.jpg)
Conflict minerals
• What are “Blood diamonds”
![Page 74: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/74.jpg)
Conflict minerals
• “blood diamonds”– Profits from the sale
of diamonds fuels the oppression and in some cases slaughter of thousands of people
– Funds rebels and terrorists
![Page 75: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/75.jpg)
DiatomiteDiatomite
![Page 76: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/76.jpg)
Diatomite—introductionDiatomite—introduction
• made of plant fossils shaped like soda straws
• silica
• looks like chalk (CaCO3)
• diatomaceous earth
![Page 77: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/77.jpg)
![Page 78: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/78.jpg)
DiatomiteDiatomite
http://www.rockdetective.org/f...
![Page 79: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/79.jpg)
DiatomiteDiatomite
http://www.maidenwell.com/
![Page 80: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/80.jpg)
Chemical compositionChemical composition
• 86% silica
• 5% sodium
• 3% magnesium
• 2% iron
![Page 81: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/81.jpg)
Diatomite—propertiesDiatomite—properties
• Light weight (hollow fossil shells)
• does not conduct heat
![Page 82: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/82.jpg)
Diatomite—usesDiatomite—uses
• Once used in dynamite• insulate steam pipes• filtration aid (swimming pools)• mild abrasive• mechanical insecticide (physico-sorptive
properties)• absorbent for liquids• Cat litter• activator in blood clotting studies• thermal insulator • plants
![Page 83: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/83.jpg)
Diatomite—substitutionsDiatomite—substitutions
• Expanded perlite• silica sand• talc• ground silica sand,• ground mica• clay• exfoliated
vermiculite
• Perlite• vermiculite• ground limestone• various clays• special brick• mineral wool• expanded perlite
![Page 84: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/84.jpg)
Diatomite—productionDiatomite—production
USGS Commodities SummaryUSGS Commodities Summary
![Page 85: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/85.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 86: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/86.jpg)
Diatomite—geologyDiatomite—geology
• Saltwater – contains a high crystalline silica content
• Fresh water lake– dry lakebeds and is characteristically low in
crystalline silica content
![Page 87: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/87.jpg)
Diatomaceous earthDiatomaceous earth
http://www.minerals.epcorp.com..
![Page 88: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/88.jpg)
Dredging is one mining methodDredging is one mining method
http://www.hi.is/HI/Stofn/Myva...
![Page 89: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/89.jpg)
SafetySafety
• drying of the hands, if handled without gloves
• highly crystalline form of silica, resulting in sharp edges
• dangerous to breathe and a dust mask is recommended when working with it
• silicosis
![Page 90: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/90.jpg)
Feldspar and nepheline syenite—introduction
![Page 91: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/91.jpg)
Feldspar and nepheline syenite—introduction
• More than 20 minerals– albite– oligoclase– andesine– labradorite– bytownite– anorthite– microcline– sanidine– orthoclase
![Page 92: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/92.jpg)
Feldspar and nepheline syenite—introduction
• low symmetry, being only monoclinic
• twin easily
• dull to rarely vitreous luster
• blocky crystals
• two directions of cleavage at nearly right angles
• XAl(1-2) Si(3-2) O8 – X is Na, Ca, K
![Page 93: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/93.jpg)
Feldspar—introduction
• Feld from field
• spar meaning easily cleaved material
• most common minerals in the Earth's crust
![Page 94: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/94.jpg)
Identification
![Page 95: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/95.jpg)
Nepheline syenite
• light-colored, silica-deficient feldspathic igneous rock
• sodium and potassium feldspars
• nepheline, no quartz
• not mined in US but in Canada
![Page 96: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/96.jpg)
Feldspar and nepheline syenite—properties
• In glass, alumina from feldspar improves product hardness, durability, and resistance to chemical corrosion
• in ceramics, feldspar is used as a flux, melting at an early stage in the firing process and forming a glassy matrix that bonds together the other components of the system
![Page 97: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/97.jpg)
Feldspar and nepheline syenite—uses
• Dimension stone
• Ceramics 55% of total world demand
• glass 35% of world demand– container– flat glass – insulation-grade fibreglass
![Page 98: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/98.jpg)
Nepheline syenite
• alumina acts as a matrix of stabilizser, enhancing the workability of molten glass, and increasing the resistance for scratching, breaking and chemical protection
• alkali acts as a flux agent, lowering the melting temperature of the batch (no need for soda ash)
![Page 99: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/99.jpg)
Feldspar and nepheline syenite—substitutions
• feldspar-silica mixtures
• clays
• talc
• pyrophyllite
• spodumene
• electric-furnace slag
• nepheline syenite
![Page 100: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/100.jpg)
Feldspar—production
![Page 101: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/101.jpg)
Feldspar—production
![Page 102: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/102.jpg)
Feldspar—production
![Page 103: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/103.jpg)
Feldspar and nepheline syenite—geology
• China• France• Italy• Thailand• Turkey • USA• Canada
65 % of the production
![Page 104: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/104.jpg)
Feldspar and nepheline syenite—procssing
• Crush
• screen
• magnetic separation
• air classify
• refined ore
![Page 105: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/105.jpg)
Specifications for glass
http://www.fineton.com/new_page_6.htm#The Nepheline Syenite for Glass Industry
![Page 106: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/106.jpg)
Fluorite/fluorsparFluorite/fluorspar
![Page 107: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/107.jpg)
FluoriteFluorite
• Latin fluo, meaning flow
![Page 108: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/108.jpg)
FluoriteFluorite—introduction—introduction• CaF2, Calcium Fluoride• halide• variable color• Luster is vitreous.• transparent to translucent.• Cleavage is perfect in 4 directions forming octahedrons.• Hardness is 4 • Fracture is irregular and brittle. • Specific Gravity is 3.1+ (heavy)
![Page 109: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/109.jpg)
FluoriteFluorite—properties—properties
• fluorospar
• ability as a flux
• ore of F
![Page 110: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/110.jpg)
FluoriteFluorite—uses—uses
• flux in steel, ceramics and aluminum processing• in the preparation of glasses and enamels • manufacture of hydrofluoric acid (electroplating,
stainless steel, refrigerant, plastics)• for carved ornamental objects• fluorinated water• gemstone
![Page 111: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/111.jpg)
FluoriteFluorite
http://mineral.galleries.com/minerals/halides/fluorite/fluorite.htm
![Page 112: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/112.jpg)
FluoriteFluorite—substitutions—substitutions
• Olivine
• dolomitic limestone
• Byproduct fluorosilicic acid
![Page 113: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/113.jpg)
FluoriteFluorite—production—production
USGS Commodities SummaryUSGS Commodities Summary
![Page 114: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/114.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 115: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/115.jpg)
FluoriteFluorite—geology—geology
• Rio Grande Rift (RGR) deposits
• Mississippi Valley type (MVT) deposits
• Sedimentary stratiform deposits
• volcanic massive sulfide deposits
• gangue in epithermal and mesothermal veins
![Page 116: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/116.jpg)
GarnetGarnet
![Page 117: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/117.jpg)
GarnetGarnet
• Latin granatus (“grain")
• possibly a reference to the Punica granatum ("pomegranate"), a plant with red seeds similar in shape, size, and color to some garnet crystals
![Page 118: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/118.jpg)
Garnet—introductionGarnet—introduction
• group of complex silicate minerals with similar crystalline structures
• A3B2(SiO4)3, where A can be Ca, Mg, Fe, Mn; B can be Al, Cr, Fe, Ti
![Page 119: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/119.jpg)
Garnet—introductionGarnet—introduction
• aluminum garnets– almandine or almandite– pyrope– grossularite– spessartite
• iron garnets– andradite
• chromium– uvarovite
![Page 120: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/120.jpg)
Garnet—propertiesGarnet—properties
• Various colors
• isometric
• specific gravity 3-4
• Luster is vitreous
• Hardness is 6.5 - 7.5
![Page 121: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/121.jpg)
http://en.wikipedia.org/wiki/GarnetAndradite
Almandine
![Page 122: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/122.jpg)
Garnet—usesGarnet—uses
• waterjet cutting, 35%
• abrasive blasting media, 30%
• water filtration, 15%
• abrasive powders, 10%
• other end uses, 10%
![Page 123: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/123.jpg)
Garnet—substitutionsGarnet—substitutions
• natural and manufactured abrasives
• Ilmenite
• magnetite
• plastics
![Page 124: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/124.jpg)
Garnet—productionGarnet—production
USGS Commodities SummaryUSGS Commodities Summary
![Page 125: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/125.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 126: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/126.jpg)
Garnet—geologyGarnet—geology
• Gneisses and schists• contact-metamorphic deposits in crystalline
limestones• pegmatites• igneous rocks• serpentinites• vein deposits• alluvial garnet
![Page 127: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/127.jpg)
GraphiteGraphite
![Page 128: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/128.jpg)
GraphiteGraphite
• Greek (graphein): to draw/write
• for its use in pencils
![Page 129: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/129.jpg)
Graphite—introductionGraphite—introduction
• C
• confused with molybdenite, which is denser and has a silver blue streak
• gray streak
• Luster is metallic to dull
• Cleavage is perfect in one direction
![Page 130: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/130.jpg)
![Page 131: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/131.jpg)
HistoryHistory
• First use of graphite: primitive man to make drawings, and by Egyptians to decorate pottery.
• Graphite processing: 1400 AD in the Haffnerzell District of Bavaria.
• Through the Middle Ages graphite was confused with galena and Molybdenite.
• First names: Plumbago (lead -silver) & black lead
• Discovered: 1565 by Gessner (recognized as a mineral), but its composition was determined in 1779 by Scheele.
![Page 132: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/132.jpg)
Graphite—propertiesGraphite—properties• Milled, drilled and turned in a lathe to a desired shape • Making Brushes• conductive• chemically stable• high strength• hardness 1-2• specific gravity 2.2• good conductor of electricity• lubricant
![Page 133: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/133.jpg)
Physical CharacteristicsPhysical Characteristics• Color is dark gray, black, or black silver. • Luster is metallic to dull. • Transparency crystals are opaque • Crystal System is hexagonal • Hardness is 1 - 2 • Specific Gravity 2.2 • Cleavage is perfect in one direction. • Fracture is flaky. • Streak is black gray to brownish gray. • Melting Point of 3,500ºC.• Graphite is an excellent conductor of heat and electricity. • Other Characteristics: thin flakes are flexible but inelastic, mineral
can leave black marks on hands and paper.• Best Field Indicators are softness, luster, density and streak.
![Page 134: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/134.jpg)
MineralogyMineralogyGraphite is a native element composed only of carbon. It has the same composition as diamond, however it has very different structures.
•Diamond crystallizes in the Isometric system X graphite crystallizes in the hexagonal system.
Source- http://www.chem.ox.ac.uk/icl/heyes/structure_of_solids/Lecture1/Lec1.html
![Page 135: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/135.jpg)
GraphiteGraphite
http://www.phy.mtu.edu/faculty/info/jaszczak/borrowdale.html
![Page 136: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/136.jpg)
Graphite—usesGraphite—uses
• Refractory applications 45% (brick and linings)
• brake linings 20%
• lubricants, 5%
• dressings and molds in foundry operations, 5%
• other uses 25%
![Page 137: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/137.jpg)
END-USESEND-USESMain uses are in refractors, lubricants, brake linings, foundry moulds, and electrodes. Non-traditional applications include expanded graphite and graphite foils (a thin graphite cloth).
Graphite Foils
Graphite Packing Expanded Graphite
Uses of natural graphite in 2004
13%
24%
8%9%
46%
refractory applications
brake linings
foundry operations
lubricants
steelmaking and other uses(pencils, battery...)
![Page 138: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/138.jpg)
Graphite—substitutionsGraphite—substitutions
• graphite powder
• scrap from discarded machined shapes
• calcined petroleum coke
• Molybdenum disulfide
• Finely ground coke with olivine
![Page 139: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/139.jpg)
Graphite—productionGraphite—production
USGS Commodities SummaryUSGS Commodities Summary
![Page 140: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/140.jpg)
USGS Commodities SummaryUSGS Commodities Summary
![Page 141: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/141.jpg)
Graphite—geologyGraphite—geology
Types of Natural Graphite :
Disseminated flake
Crystalline vein (lump or high crystalline graphite)
Amorphous
Graphite occurs in many types of igneous, sedimentary & metamorphic rocks. The more important are those found in metasomatic –hydrothermal deposits, & in sedimentary rocks that have been subjected to regional or thermal metamorphism.
Associated Minerals include quartz, calcite, micas, iron meteorites, and tourmalines.
![Page 142: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/142.jpg)
GeologyGeologyFlake graphite:• is found in metamorphic rocks uniformly distributed through the ore
body or in concentrated lens shaped pockets. • Graphite flake occurs as a scaly or lamella form in certain metamorphic
rocks such as limestone, gneisses and schists. • Carbon concentrations vary between 5% and 40%. • Flake graphite occurs in most parts of the world. Notable deposits are
Canada, Brazil, Madagascar, Australia, USA(Texas-1980, Alabama &Pennsylvania-1960’s), Germany
• Flake: marble, gneiss, and schist (most common rock types)
Source -http://www.alibaba.com/catalog/10876290/Natural_Flake_Graphite.html
![Page 143: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/143.jpg)
Crystalline vein graphite:• is believed to originate from crude oil deposits that through time,
temperature and pressure have converted to graphite. • Vein graphite is found along the intrusive contacts of pegmatites
with limestone. • The vein fissures are typically between 1cm and 1 m thick, and are
normally > 90% pure. • Although this form of graphite is found all over the world, it is only
commercially mined in Sri Lanka.
GeologyGeology
Source - http://www.asbury.com
![Page 144: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/144.jpg)
Geology Geology Amorphous graphite: • Amorphous graphite is found as minute particles in beds of
mesomorphic rocks such as coal, slate or shale deposits. • The graphite content ranges from 25% to 85% dependent on the
geological conditions. • Most of the amorphous deposits with economic importance are
formed by metamorphism of coal or carbon rich sediments. • Notable occurrences are in Mexico, North Korea, South Korea and
Austria.
Source - http://kuroko.mus.akita-u.ac.jp/sampimag/11767e.htm
![Page 145: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/145.jpg)
Artificial GraphiteArtificial Graphite
• Synthetic graphite can be produced from coke and pitch.
• Synthetic Graphite consists mainly of graphitic carbon that has been obtained by graphitisation, heat treatment of non-graphitic carbon, or by chemical vapour deposition from hydrocarbons at temperatures above 2100K .
• Synthetic Graphite tends to be of higher purity though not as crystalline as natural graphite.
• On the whole, synthetic graphite tends to be of a lower density, higher porosity and higher electrical resistance.
• Its increased porosity makes it unsuitable for refractory applications.
Source - http://www.intertrade.com.
![Page 146: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/146.jpg)
Mining MethodMining MethodGraphite is commonly extracted through open-pit methods. In some cases, it has been extracted through underground mining (vein deposits in Sri Lanka).
Mining - Graphite ore is extracted with the use of shovels & bulldozers that load dump trucks with the crude ore.
Mechanical concentration - The ore is crushed by a primary crusher and then submitted to a series of roll crushers and classifiers to remove the oversizes and gangue. Flotation is used for the mechanical separation of the graphite from impurities present in the ore. The cycle mill-flotation is repeated until a grade between 87 -96% of carbon is reached.
Chemical concentration - Concentration with the use of chemical agents is used to remove impurities that remain in the graphite after the mechanical concentration process. Some firms make high purity graphite (98% - 99%carbon) by leaching concentrate with strong acids or alkalis.
Primary Crusher
Mill
Flotation Cells
Dryers
![Page 147: ME551/GEO551 Geology of Industrial Minerals Spring 2011](https://reader035.vdocument.in/reader035/viewer/2022062410/56815a76550346895dc7df19/html5/thumbnails/147.jpg)
Read the following sections in the Read the following sections in the IM text.IM text.
• Chromite
• Gypsum
• Helium
• Iodine
• iron ore
• Kyanite
• lithium