US Copper Corp Announces Results from Moonlight Drilling
US Copper Corp Announces Results from Moonlight Drilling
TORONTO, CANADA, May 15, 2024 – US Copper Corp (“ US Copper” or the “ Company”)
(TSX Venture: USCU) (OTCQB: USCU F) (Frankfurt: C73) is pleased to announce results from
the 15-hole shallow drill program last fall on its Moonlight de posit at the Moonlight-Superior
Copper Project in North-East California.
Highlights
1. Mineralized drill hole intercepts were sub mitted for sequential copper assays, and acid
soluble copper was identified in 14 of 15 holes, including one intercept of 205 feet (“ ft”)
of 0.644% recoverable copper;
2. Results confirmed a small oxide cap covers the large Moonlight sulfide deposit. This cap
had been considered waste rock by previous operators;
3. Soluble copper averaged 91% of total copper; and
4. Acid soluble copper greater than 0.2% occurs over an area of 2, 000 ft by 1500 ft to an
average depth of greater than 150 ft.
These results are now being reviewed by an independent engineering firm to determine:
1. Parameters for further metallurgical testing;
2. A new resource calculation for the oxide mineralization at Moonlight; and
3. The economic viability of an oxide mining operation combining b oth the Engels and
Moonlight oxide caps.
Management Commentary
“Results from our exploration dr ill program at Moonlight con firm a near-surface copper oxide
cap sits above the larger copper sulfide deposit below. These ty pes of copper oxide deposits are
found in the major copper mining districts of the world and can typically be economically
extracted, usually through low-impact surface mining, and processed at lower cost than copper
sulfide ores. Furthermore, acid leaching of ox ide copper produces high grade copper cathodes,
with grade A cathode typica lly selling for a premium. ” commented Stephen Dunn, President and
CEO of US Copper.
“With the recent addition of copper to the U.S. critical minerals list, we look forward to conducting
a preliminary economic assessment to evaluate the viability of a copper oxide mining operation at
the past-producing Engels deposit, towards advanc ing a secure and responsible domestic supply
of U.S. mined copper,” concluded Mr. Dunn.
Table 1: Summary of drill hole data
(* Total leachable copper is the total of the sulfuric acid recovery and the cyanide recovery)
Moonlight Oxide Assays - 2023
Total Total* Sulfuric aci dCyanide
Copper Leachable Leachable leachable
DH# from to
Interval
(ft)
Cu-OG-
4A-%
Total
Leach %
Cu-AL/AA-
H2SO4-%
Cu-
CN/AA-
CN-%
23MRC16 0 90 90 0.12
Inc 40 60 20 0.27 0.225 0.042 0.183
23MRC17 0 90 90 0.22
Inc 35 70 35 0.47
Inc 55 75 20 0.71 0.646 0.052 0.594
23MRC18 0 60 60 0.15
Inc 35 55 20 0.37 0.334 0.053 0.281
23MRC19 0 100 100 0.32
Inc 10 100 90 0.35 0.31 0.057 0.253
23MRC20 0 50 50 0.46
Inc 10 30 20 0.55 0.527 0.262 0.265
Inc 10 50 40 0.55 0.524 0.162 0.362
23MRC21 0 60 60 0.34
Inc 20 40 20 0.37 0.316 0.239 0.077
Inc 40 60 20 0.49 0.407 0.074 0.333
Inc 20 60 40 0.43 0.362 0.157 0.205
23MRC22 0 100 100 0.38
Inc 60 100 40 0.86 0.838 0.067 0.771
23MRC23 0 100 100 0.19
Inc 65 85 20 0.47 0.464 0.03 0.434
Inc 45 100 55 0.30 0.278 0.025 0.253
23MRC24 0 80 80 0.29
Inc 15 35 20 0.53 0.521 0.476 0.045
Inc 15 55 40 0.43 0.422 0.267 0.155
Inc 15 75 60 0.34 0.336 0.185 0.151
23MRC25 0 470 470 0.38
Inc 10 215 205 0.80 0.644 0.066 0.578
Inc 10 255 245 0.69
23MRC26 0 130 130 0.22
Inc 60 125 65 0.36 0.341 0.022 0.319
23MRC27 0 500 500 0.06
Inc 45 70 25 0.39 0.347 0.042 0.305
Inc 95 120 25 0.26 0.241 0.028 0.213
23MRC28 0 370 370 0.09
Inc 35 55 20 0.22 0.210 0.033 0.177
Inc 130 155 25 0.22 0.207 0.022 0.185
23MRC29 0 120 120 0.36
Inc 20 120 100 0.42 0.392 0.100 0.292
23MRC30 0 110 110 0.04
Sequential copper assays
Leach Soluble Copper
Background
The Moonlight deposit is primarily a copper sulfide deposit hos ted in the Lights Creek stock of
Quartz Monzonite ( QM) which had intruded Triassic - Jurassic metavolcanics. The res ource
consists of an earlier stage of mineralization with disseminate d sulfide minerals in the QM and a
later stage structurally controlled mineralization of tourmalin e vein and breccia structures of
multiple orientations that house sulfides. A small oxide cap, d ominantly malachite with some
chalcocite and native copper, covers the surface of the deposit . In the 1970s Placer-Amex had
estimated a resource for the oxide cap at 12.2 million tons at 0.54% copper. This estimate is
historical in nature though and cannot be relied on. With the r ecent drilling at Moonlight, a new
resource estimate will now be calculated for the oxide cap to update the current moonlight resource.
The Moonlight sulfide deposit hosts a current National Instrument 43-101 (“NI 43-101”) indicated
resource of approximately 252 million tons (154 million tonnes) averaging 0.25% copper and 0.07
oz/silver per ton, and an inferred resource of 109 million tons (62 million tonnes) averaging 0.24%
copper and 0.08 oz/silver per ton, both above a US$6.25 net sme lter return cut-off. Contained
indicated resources are 1.272 billion pounds of copper and 18 million ounces of silver, and inferred
resources of 534 million pounds of copper and 9 million ounces of silver. The Moonlight sulfide
deposit remains open to the south and at depth. This resource e stimate is contained in the NI 43-
101 Technical Report and Preliminary Economic Assessment (“PEA”) for the Moonlight Deposit,
Plumas County, California, by Tetra Tech, dated April 12, 2018, available on US Copper’s website
and on SEDAR.
US Copper had this PEA prepared on its Moonlight deposit in 201 8 and it demonstrated positive
economics at $3.15 per pound copper. It was also determined that providing higher grade ore from
our Superior and/or Engels deposits into the Moonlight mine plan would substantially enhance the
Project’s economics by potentially increasing cash flows in the initial years of production. The
recently completed drill program at Superior in 2021and at Enge ls and Moonlight in 2023 were
designed to better define any higher grade ore at these deposit s for potential starter pits for the
Moonlight plant. Ultimately, the updated Engels and Superior resources will be incorporated into
a revised Moonlight PEA.
Technical Information and Quality Control & Quality Assurance
US Copper personnel regularly obser ve procedures including the boxing of core at the drill site.
Core is then securely delivered to the core logging and storage facility in Crescent Mills CA (~10
miles from the drill sites). The core is logged, magnetically scanned, and photographed. Periodic
samples are collected for specific gravity testing and petrographic analysis. The core is then sawn
in half. One half is bagged with appropriate documentation and securely transported to the ALS
lab in Reno, NV. To ensure that proper QAQC accompanies the an alyses appropriate QAQC
elements are included in each batch of samples. The QAQC elements consist of certified standards,
duplicate analyses and certified coarse blanks or blank materia l that has been documented to be
barren for gold and base metals.
Qualified Person
The scientific and technical content of this press release has been reviewed and approved by
George Cole, M.Sc., Director of US Copper who is a "Qualified P erson" as defined in NI 43-101
Standards of Disclosure for Mineral Projects. George Cole is a Registered Professional Geologist
through AIPG (CPG-11687).
About US Copper Corp
US Copper controls approximately 13 square miles of patented and unpatented federal mining claims in the
Light’s Creek Copper District in Plumas County, NE California; essentially, the entire District. The District
contains substantial copper (silv er) sulfide and copper oxide r esources in three deposits – Moonlight,
Superior and Engels, as well as several partially tested and untested exploration targets.
The Superior and Engels Mines operated from about 1915-1930 pro ducing over 161 million pounds of
copper from over 4 million tons of rock containing 2.2% copper with silver and gold credits.
The Moonlight Deposit was discovered and drilled by Placer Amex during the 1960’s. Details of the
resources on US Copper’s property and the parameters used to calculate them can be found in the "Technical
Report and Preliminary Economic A ssessment for the Moonlight De posit, Moonlight-Superior Copper
Project, California, USA" dated April 12, 2018, on both the company’s website at www.uscoppercorp.com
or on www.sedar.com under the US Copper Corp profile.
The Moonlight PEA, prepared by Tetra Tech Inc., had the following highlights:
After-tax NPV of US$179M at an 8% discount rate and a $3.15 copper price.
After tax IRR of 14.6%
Initial Capital Cost: US$513M, including a contingency provision in the amount of US$71M
Plant Processing Rate: 60,000 tons per day (STPD)
Average Copper Recovery: 86.0%
Mine Life: 17 years, based on the existing Mineral Resource estimate
Life of mine copper production of 1.5 billion pounds
The Superior deposit is not included in the Moonlight PEA and it hosts a current NI 43-101 inferred mineral
resource of 57 million metric tonnes at an average copper grade of 0.41%. Note no silver or gold were
included as part of this resource.
Please note the PEA is preliminary in nature and includes inferred mineral resources that are considered too
speculative geologically to have the economic considerations applied to them that would enable them to be
categorized as mineral reserves. Furthermore, there is no certainty that the preliminary economic assessment
will be realized. Mineral resources that are not mineral reserv es do not have demonstrated economic
viability. Readers are encouraged to read the technical report.
For Further Information Contact:
Mr. Stephen Dunn, President, CEO and Director, US Copper Corp ( 416) 361-2827 or email
Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the
TSX Venture Exchange) accepts responsibility for the adequacy or accuracy of this press release.
This press release contains forward-looking statements within the meaning of applicable Canadian and U.S. securities
laws and regulations, including statements regarding th e future activities of the Company. Forward-looking
statements reflect the current beliefs and expectations of management and are identified by the use of words including
“will”, “hopes”, “anticipates”, “expected to”, “plans”, “p lanned”, “intends” and other similar words. Actual
results may differ significantly. The achievement of the resu lts expressed in forward-looking statements is subject to
a number of risks, including those described in the Company’s management discussion and analysis as filed with the
Canadian securities regulatory authorities which are availabl e at www.sedar.com. Investors are cautioned not to
place undue reliance upon forward-looking statements.