candelaria project stephen piurkowsky

Zhaoshan Mentor Meeting 3/8/21

Michael Kirschbaum, Mary Carr, Zhaoshan Chang, Stephen Piurkowsky, Phil Nickerson (Rio Tinto), Adam

Pacey (Rio Tinto), Paul Agnew (Rio Tinto)

Candelaria Project – Stephen Piurkowsky

C-O Isotope results: See slides

Stephen says the balance of data suggests a magmatic source for the waters: Magmatic hydrothermal.

His data and IOCG article support his conclusion.

Paul Agnew: have you gotten lab QC data that indicates that this is good data? It isn’t really showing the

trends they expected to see. Stephen was also expecting more. Yes, it seems the data is good. The data

from an Australian lab and the VT lab appear to match.

Zhaoshan commented that IAB is forcing them to work with VT. The turnaround time is slow

Paul Agnew says their data is showing trends and perhaps they should send them to ASU. As a

geochemist he is suspicious of the findings. Paul would like to see 10-15 sent off to Arizona.

Phil: What do you think about the difference between wall rock and veins? The wall rock may show

more consistent trends. Perhaps because the sampling might be more consistent for the wall rock than

the veins.

What about e-w versus n-s trends? Neither seems to show a clear trend.

Adam: Seeing the samples in map view with a detailed map might show some of the controls on the

trends better.

Stephen: Has looked at various things such as cretaceous dikes.

Adam: Thanks for pointing out that weathered veins are not good for sampling

Preliminary C-O Isotope ResultsMarch 8th, 2021

byStephen Piurkowsky

C-O plot

Marine carbonate <0.6 Ga

MagmaticCO2

Veins

Wallrock

C-O plot

A lot of samples from mineralization plot here

Rollinson, 1993

C-O Comments

Marine carbonate <0.6 Ga

MagmaticCO2

Groundwater Oxygen isotope contamination? Without C?

Veins/wall rock interaction with magmatic fluids causing depletion?

Two mixing trends? Groundwater and magmatic fluids? Since these are distal samples, I’m betting that there is going to be groundwater signal in almost all, but the degree of fractionation should vary

MagmaticWaters

Can also see three populations in prop plot

Depleted/proximal wallrocks

Transitionary wall rock?

Normal wall rock

• General maps are next, with weathered samples excluded

Vein

= relevant deposits

Rock

= relevant deposits

= relevant deposits

Vein

Rock

= relevant deposits

Distance – T#1

I don’t know how to get the x axis (distance) fixed…

Rock samples from Pabellon Fm.Are known to have abnormally low C-O signature due to metamorphism by overlying sill/volcanics

Distance – T#2

Distance – T#3 (southernmost E-W traverse)

Distance – T#5

Distance – T#6 (falla lar)

Distance – T#7 (san gregorio)

d18O comments

• Traverse #1 seems to have the best trend, but is also one of the closest to mineralization

• Seems like the O signal only goes about 2-3km, either along faults or crosscutting stratigraphy

• #3 and #5 are interesting, as there seems to be a signal at far distances. However, for #5 there is technically closer mineralization (at carola) than the Candelaria pit (where the distance is currently based on). For #3, im not sure, but perhaps there are veins related to faults as the traverse is close to faults.

• Anomalous samples are related to weathering

Distance vs d13C – T#1

Really weird patterns here –probably related to ocean chemistry

All values within typical values reported for cretaceous carbonates

Distance vs d13C – T#2

Distance vs d13C – T#3

Distance vs d13C – T#5

Distance vs d13C – T#6 (falla lar)

Distance vs d13C – T#7 (san gregorio)

d13C comments

• Some anomalous samples may be from weathered veins/veins related to groundwater

• Overall variation much less than d18O, consistent with literature

Sample δ13C δ18O NotesCDL19-014-V -1.95 -10.9CDL19-014-W 0.49 -6.6CDL19-015-V 1.38 -7.1CDL19-015-W 0.08 -6.4CDL19-016-V -1.47 -1.9CDL19-016-W -0.32 -8.9CDL19-017-V 1.79 0.6CDL19-017-W 0.20 -6.9CDL19-019-V 5.87 -2.5CDL19-019-W 2.13 -16.8CDL19-021-V -0.62 -17.1CDL19-021-W -1.24 -15.8CDL19-022-W -2.07 -13.9CDL19-023-V 2.50 -1.5 ReplicatedCDL19-023-W2 -0.24 -14.3 ReplicatedCDL19-023-W4 -1.28 -13.7CDL19-026-W 0.30 -13.1CDL19-027-V Still needs to be runCDL19-027-W 0.29 -15.1CDL19-028-V -2.57 -15.2CDL19-028-W 0.64 -15.0CDL19-029-V 1.86 -6.2CDL19-029-W 1.15 -7.1CDL19-030-V 0.71 -9.3CDL19-030-W 0.84 -11.0CDL19-031-W 0.27 -10.7CDL19-031-V Still needs to be runCDL19-032-V Still needs to be runCDL19-033-V 0.67 -14.3CDL19-033-W 0.73 -14.3CDL19-034-V -0.31 -11.4CDL19-034-W -0.40 -8.1CDL19-035-V -5.33 -11.3CDL19-035-W -4.98 -8.9CDL19-036-V 0.74 -9.7CDL19-036-W 1.26 -6.6CDL19-037-V Still needs to be runCDL19-037-W 0.73 -8.6CDL19-038-V -0.09 -7.4CDL19-038-W 0.77 -5.8CDL19-039-V -0.46 -9.0CDL19-039-W 0.11 -5.9

CDL19-040-W -0.77 -7.7CDL19-041-V 0.92 -17.9CDL19-041-W 0.02 -10.6CDL19-042-W 1.52 -8.9CDL19-043-V 2.20 -15.4CDL19-043-W 2.17 -5.5CDL19-044-V 1.00 -7.3CDL19-044-W 1.12 -7.7CDL19-045-W 1.76 -15.9CDL19-046-W 2.19 -10.1CDL19-047-V 1.81 -11.1CDL19-047-W 1.52 -7.7CDL19-048-V 1.13 -9.6CDL19-048-W 0.52 -8.7CDL19-049-V -0.35 -5.1CDL19-049-W 0.60 -7.1CDL19-050-W 0.92 -6.8CDL19-051-V 0.32 -10.3CDL19-051-W Needs to be rerun; did not pass data quality controlsCDL19-052-W 1.60 -6.8CDL19-053-V 1.49 -7.8CDL19-053-W 1.58 -8.0CDL19-054-V 1.76 -11.6CDL19-054-W 1.48 -11.1CDL19-055-V -0.66 -10.1CDL19-055-W 1.03 -10.1CDL19-056-V 1.42 -17.3CDL19-056-W 1.65 -6.3CDL19-057-V 1.59 -11.4CDL19-057-W 1.93 -6.8CDL19-058-V 2.22 -8.5CDL19-058-W 2.06 -5.6CDL19-059-V 1.84 -10.0CDL19-059-W 1.54 -5.3CDL19-060-V -4.05 -14.1CDL19-061-V -0.27 -14.1CDL19-061-W 0.73 -10.4CDL19-062-V 1.82 -10.4CDL19-062-W 1.98 -7.5CDL19-063-V 1.70 -20.1CDL19-063-W 1.94 -6.3CDL19-064-V 1.20 -19.8CDL19-064-W 1.28 -9.9

CDL19-065-V 1.18 -19.7CDL19-065-W 1.65 -7.1CDL19-066-V 1.69 -8.4CDL19-066-W 1.51 -6.8CDL19-067-V 0.03 -13.9CDL19-067-W 0.73 -7.1CDL19-068-W Needs to be rerun; did not pass data quality controlsCDL19-069-W Needs to be rerun; did not pass data quality controlsCDL19-070-V -1.12 -10.8CDL19-070-W -3.17 -6.2CDL19-071-V 1.74 -15.1CDL19-071-W 1.82 -8.2CDL19-072-W -6.31 -8.1CDL19-074-V -0.26 -12.6CDL19-074-W -0.08 -11.6CDL19-075-V -2.25 -14.2CDL19-075-W -0.98 -11.2CDL19-077-V -1.40 -15.9CDL19-077-W 1.93 -13.2CDL19-078-W -0.19 -13.1CDL19-079-V -1.20 -16.4CDL19-079-W -3.09 -10.8CDL19-080-V -3.26 -20.2CDL19-080-W 0.20 -10.2CDL19-142-V 0.42 -10.2CDL19-229-W -1.32 -7.7LEDO36-181-W -3.36 -16.5LEDO36-184-W -1.26 -13.5LEDO36-281-W -1.53 -17.7LEDO36-333-W -6.07 -17.7LEDO36-381-W -1.77 -15.5LEDO36-429-W -0.58 -16.3LEDO36-494-V -0.12 -15.5LEDO36-494-W -0.68 -15.3REDO-023-V 3.07 -1.3REDO-023-W2 0.34 -12.4REDO-023-W4 -1.16 -13.7 ReplicatedREDO-23-V 3.10 -0.7REDO-23-W4 -1.01 -13.5

Bingham Project – Michael Kirschbaum

ALS geochemistry RIOSHALO package only requires 0.25g samples. Michael is going for 3-5g so that he

can also do other Geochem. This is requiring that he samples multiple veins.

Adam says keep the samples to 1-2 kilos, they will keep 250grams.

Paul suggested: Below detection values are important – assign a below detection values a number so

that you know that it is there. Don’t lose the data off the plot. Adam gave some specific suggestions.

Permeability study: Zhaoshan got a senior engineer from an oil company to help with the problem. He is

now an affiliated faculty. Had their first meeting with him. Got a quote from commercial lab for perm.

20 samples at Core Lab will be $5400.

Sulfur analysis: developed a method showed a plot of data. Can now detect down to 70 or 80 ppm

concentrations. MS/MS mode.

Adam: Third site discussion with Paul will happen offline and he will get back to Michael.

Phil: Looking for data on a magnesium skarn. Zhaoshan said he will send along references. They are

quite different from a calcic skarns. Lots of serpentines involved.

The are still looking for some of the cores that Michael would like to use. They are not catalogued, so it

is taking time. This is related to Stockton. They will have to move a lot of cores and it will be time

intensive for the guys with the forklift.

Further discussion of finding core samples at the mine site between Michael and Phil.

Bingham Update: March 2021

Mike Kirschbaum

Distal Vectors to Porphyry in Carbonate Rocks

Colorado School of Mines

Progress Overview• Work in February focused on sample preparation & preliminary analysis of 6 samples• Billets cut for 42 thin sections (TS) (39 field samples, 3 DDH samples):

• 7 TS complete• 7 more TS should be complete this week• 30 additional TS to be completed in coming weeks

• Additional DDH samples to have billets cut this week (~20 samples selected, will choose 5-10)• These will represent “proximal” end members (mainly skarn/marble hosted)

• Petrography and selection of LA-ICP-MS “spots” in progress• 6 TS marked and analyzed by LA-ICP-MS (next slides)• These will also be re-analyzed; issues with S detection has been fixed

• Drilling of veins for ALS geochemistry (RIOSHALO package) in progress: trying to get 3-4g/sample

• Mike K trained on:• LA-ICP-MS sample preparation and spot programming• Data reduction using IOLITE software

Preliminary LA-ICP-MS: Sample Locations

Bingham

Stockton

XXXm = map distance from QMP

340m

540m

1835m

2550m

5813m9636m

Anomalous Sample

• 6 Samples analyzed on LA-ICP-MS• Next slides will be keyed to these

distance numbers• Distance is straight line on map

from SW corner of Quartz Monzonite Porphyry (QMP)

• QMP is syn-mineral at Bingham

Preliminary LA-ICP-MS: Veins-1

-youngest

-oldest

Mg Si P

S Sc Cr

Mn Fe Co

• Note: trend lines are schematic

• Trends in:• Mg• Mn• Fe

• Anomaloussampleignored fornow

Anomalous Sample

-youngest

-oldest

Preliminary LA-ICP-MS: Veins-2

Ni Cu Zn

As Rb Sr

Y Mo Ag

• Trend inYttrium

-youngest

-oldest

Preliminary LA-ICP-MS: Veins-3

Ba La Ce

Pr Nd Sm

Eu Gd Tb

• Some trends• Ba• REE

-youngest

-oldest

Preliminary LA-ICP-MS: Veins-4

Dy Ho Er

Tm Yb Lu

Pb Th U

• Some trends• Ba• REE

Preliminary LA-ICP-MS: Discussion• Too few samples to strongly discern trends, but some look promising

• Apparent increase and then decrease within ~3km for Mn, REE, Ba• Sharp decrease in Fe with distance from QMP• More gradual decrease in Mg from QMP

• Outliar at 5813m with anomalous REE; also had high Si, P, Cr and Sc (monazite/xenotime inclusions?)• No nearby prospects• Seems like other limestone samples with white calcite veins

BM20-018