FORMING MINERALSAnd mining them…

MINERALS FROM WATER

Saltwater Evaporation

• water evaporates=

minerals left behind

• Ex. gypsum, halite

Halite= rock salt

Surface/Ground Water

• Dissolved minerals in surface/ground

water travel to lakes/seas

• Crystallize on the bottom= limestones

• Ex. calcite, dolomite

• LOTS of limestone found in this area of MN

METAMORPHIC ROCKS

• Pressure & temperature

change chemical makeup of rocks

• Ex. calcite, garnet, graphite,

hematite, magnetite, mica, talc

HOT-WATER SOLUTIONS

• Reacts with minerals=

hot liquid solution

• Dissolved metals,

elements crystalize

• Ex. gold, copper, sulfur,

pyrite, galena

• Black smokers…

Pegmatites

• Magma goes up

• Forms tear-shaped bodies

• Hot fluids= formations of huge crystals

• Can be several meters across

• Ex. topaz, tourmaline (gems)

Plutons

• Magma goes up, stops before

reaching surface

• Cools slowly= millions of crystals

• Ex. mica, feldspar, magnetite, quartz

FORMED FROM MAGMA

MINING MINERALS

A lot harder than you’d think…

MINE MORE THAN YOU NEED

• Mine ore and extract the

valuable stuff from inside

• Ore= mineral deposit

big/valuable enough to

earn profit

TWO MINING OPTIONS

Surface

• At or near the surface

• Open pits

• Strip mines

• Quarries

• Finding minerals

• Copper ores

• Bauxite (contains aluminum)

Deep

• Way down inside Earth

• Dig passages underground

• Ex. diamonds, coal

COMMON USES OF MINERALS

Chalcopyrite

Metal= copper=

coins, wire

Galena

Metal= lead=

batteries, paints

Chromite

Metal= chromium=

stainless steel, cast

iron, leather tanners

Aside from gems (rare, pretty mineral crystals; must be hard enough to be cut)

RECLAMATION

Returning land to its natural state

Law as of 1970

Mineral ores= nonrenewable

Recycle!

ROCKS

Solid mixture of crystals (one+ minerals)

CAN be made of organic materials

WHAT ARE ROCKS USED

FOR???

• Tools

• Hammers

• Arrowheads

• Scrapers

• Knives

• Buildings

• Piecing together history (fossils)

See pgs.82-83 for more information

CLASSIFYING ROCKS

Composition

• What minerals a rock contains

Texture

• Size, shape, position of grains

• Small grains (silt, clay)= fine

• Large grains (pebbles)= coarse

• In between= medium

Breaking down igneous, metamorphic, and sedimentary even more

Clues on how and where a rock was formed