Excelsior Mining Announces Assay Results from JCM Stage 1 Drilling with Nuton, a Rio Tinto Venture
NEWS RELEASE
Excelsior Mining Announces Assay Results from JCM Stage 1 Drilling with Nuton, a Rio
Tinto Venture
October 16, 2023
Excelsior Mining Corp. (TSX: MIN) (FSE: 3XS) (OTCQB: EXMGF) ("Excelsior" or the “Company”)
is pleased to announce assay results at the Johnson Camp Mine (JCM) from the Stage 1 drilling with
Nuton LLC (“Nuton”), a Rio Tinto venture. The program consists of drilling approximately 6,000 feet of
PQ core, primarily for the purposes of further metallurgical evaluation. The samples from the drill program
will be processed for mineralogy and tested using the Nuton™ process. The program is being funded by
Nuton and carried out by Excelsior in connection with the previously announced Option to JV Agreement.
“We are very happy with the results of the Stage 1, Phase 2 drilling with all holes finishing in mineralization
and intersecting over 200 feet (true thickness) of good grades, with all lower intersections averaging over
0.55% total copper (highlighted below). The results are sufficient to warrant some additional drilling to the
south which will commence this month. Mineralogical and metallurgical testing has also commenced.,”
comments Roland Goodgame, Senior Vice President Business Development.
All 13 planned holes have been drilled using diamond drill rigs to generate PQ sized core and assays
have been returned for all holes. The Stage 1 program is divided into two phases. Phase 2 holes
(designated PH2) were drilled above the mineralization from the east side of the Burro pit. These holes
were designed to test the extent of the mineralization and provide further representative metallurgical
samples. Assay results are included in Table 1 below. Stage 1, Phase 1 drilling results were previously
announced on September 14, 2023.
Table 1. Assay results.
Hole ID From (Ft) To (Ft) Interval (Ft) True Thickness (Ft) TCu%
PH2-1 10 110 100 72.0 0.25
260 650 390 280.8 0.51
PH2-2 0 110 110 78.1 0.27
220 250 30 21.3 0.54
280 602 322 228.6 0.48
PH2-3 0 80 80 56.8 0.22
236 570 334 237.1 0.60
PH2-4 6 72.5 66.5 45.9 0.26
240 546 306 211.1 0.58
PH2-5 170 548 378 272.2 0.61
PH2-6 18 50 32 21.3 0.19
190 581 391 260.4 0.63
PH2-7 120 547 427 303.2 0.70
PH2-8 130 522 392 236.8 0.49
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All samples are prepared from manually split or sawn PQ core sections on site in Arizona. Split drill core
samples are then sent to independent laboratory Skyline Assayers & Laboratories in Tucson, Arizona for
Total Copper and Sequential Copper analyses. Standards, blanks, and duplicate assays are included at
regular intervals in each sample batch submitted from the field as part of an ongoing Quality
Assurance/Quality Control Program. Pulps and sample rejects are stored by Excelsior for future
reference.
About The Johnson Camp mine
The Johnson Camp Mine (“JCM”) has historically been an open pit, heap leach operation since Cyprus
Minerals opened the property in the 1970’s. The operation includes two open pits, a two-stage crushing-
agglomerating circuit, a fully functioning SX-EW plant capable of producing 25 million pounds of cathode
copper per year, a complete set of PLS and raffinate ponds, and full infrastructure (ancillary facilities,
access, power, water, and communications).
An updated Preliminary Economic Assessment (PEA) incorporating conventional sulfide leaching (not
Nuton) technology was announced February 22nd 2023. Mining of JCM would be by traditional open pit.
The highlights of the PEA financial model, using a copper price of $3.75/lb, shows an after-tax NPV of
US$180 million (7.5% discount rate), and an after-tax IRR of 30.4%. The results are tabulated below.
Mine Life and post mining processing ~20 years
Heap Leach Material Mined 85.2 M ton
Total Copper Grade (CuT%) 0.37%
Average LOM Total Copper Recovery* 77%
Cu Produced 492 M lb
Total Tonnage Mined 196 M ton
Initial Mine Capital $58.9 million
Total Operating Cash Cost ($/lb Cu)** $2.24
After-Tax NPV/IRR (7.5% discount rate) $180.0M / 30.4%
*Total copper recovery includes a combination of oxide, transition
and primary sulfide mineral recoveries.
** Includes all operating costs, site G&A, royalties, non-income
taxes, salvage, reclamation and closure.
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. There is no certainty that the conclusions reached in the PEA will be
realized. Mineral resources that are not mineral reserves do not have demonstrated economic viability.
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QUALIFIED PERSON
Excelsior's exploration work on the Johnson Camp mine is supervised by Stephen Twyerould, Fellow of
AUSIMM, President and CEO of Excelsior and a Qualified Person as defined by NI 43-101. Mr. Twyerould
has reviewed and is responsible for the technical information contained in this news release. Mr.
Twyerould has verified the data disclosed in this news release, including sampling, analytical and test
data underlying the information disclosed in this news release. Mr. Twyerould has verified that the results
were accurate from the official assay certificates provided to Excelsior.
About Excelsior Mining
Excelsior “The Copper Solution Company ” is a mineral exploration and production company that owns
and operates the Gunnison Copper Project in Cochise County, Arizona. The project is a low cost,
environmentally friendly in-situ recovery copper extraction project that is permitted to 125 million pounds
per year of copper cathode production. Excelsior also owns the past producing Johnson Camp Mine and
a portfolio of exploration projects, including the Peabody Sill and the Strong and Harris deposits.
For more information on Excelsior, please visit our website at www.excelsiormining.com.
About Nuton
Nuton is an innovative venture that aims to help grow Rio Tinto's copper business. At the core of Nuton
is a portfolio of proprietary copper leach related technologies and capability - a product of almost 30 years
of research and development. Nuton offers the potential to economically unlock copper from primary
sulfide resources worldwide through leaching, achieving market-leading recovery rates, contributing to
an increase in copper production from copper bearing waste and tailings, and achieving higher copper
recoveries on oxide and transitional material. One of the key differentiators of Nuton is the potential to
produce the world's lowest impact copper while having at least one Net Positive impact at each of our
deployment sites, across our five pillars: water, energy, land, materials and society.
For further information regarding this press release, please contact:
Excelsior Mining Corp.
Concord Place, Suite 300, 2999 North 44th Street, Phoenix, AZ, 85018.
Shawn Westcott
T: 604.365.6681
www.excelsiormining.com
Cautionary Note Regarding Forward-Looking Information
This news release contains "forward-looking information" concerning anticipated developments and events that may
occur in the future. Forward looking information contained in this news release includes, but is not limited to,
statements with respect to: (i) the intention to deploy the Nuton® technology at the Johnson Camp mine and future
production therefrom; (ii) the timeline for additional assay results; (iii) the results of the preliminary economic
assessment on Johnson Camp; (iv) future production and production capacity from the Company’s mineral projects;
(v) the prospects of mining and leaching predominantly sulfide copper mineralization in partnership with Nuton; (vi)
future drill results; and (vii) the development timeline to mine Johnson Camp.
In certain cases, forward-looking information can be identified by the use of words such as "plans", "expects" or
"does not expect", "budget", "scheduled", "estimates", "forecasts", "intends", "anticipates" or "does not anticipate",
or "believes", or variations of such words and phrases or state that certain actions, events or results "may", "could",
"would", "might", "occur" or "be achieved" suggesting future outcomes, or other expectations, beliefs, plans,
objectives, assumptions, intentions or statements about future events or performance. Forward-looking information
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contained in this news release is based on certain factors and assumptions regarding, among other things, the
estimation of mineral resources and mineral reserves, the realization of resource and reserve estimates,
expectations and anticipated impact of the COVID-19 outbreak, copper and other metal prices, the timing and
amount of future development expenditures, the estimation of initial and sustaining capital requirements, the
estimation of labour and operating costs (including the price of acid), the availability of labour, material and acid
supply, receipt of and compliance with necessary regulatory approvals and permits, the estimation of insurance
coverage, and assumptions with respect to currency fluctuations, environmental risks, title disputes or claims, and
other similar matters. While the Company considers these assumptions to be reasonable based on information
currently available to it, they may prove to be incorrect.
Forward looking information involves known and unknown risks, uncertainties and other factors which may cause
the actual results, performance or achievements of the Company to be materially different from any future results,
performance or achievements expressed or implied by the forward-looking information. Such factors include risks
inherent in the construction and operation of mineral deposits, including risks relating to changes in project
parameters as plans continue to be redefined including the possibility that mining operations may not be sustained
at the Gunnison Copper Project, risks relating to variations in mineral resources and reserves, grade or recovery
rates, risks relating to the ability to access infrastructure, risks relating to changes in copper and other commodity
prices and the worldwide demand for and supply of copper and related products, risks related to increased
competition in the market for copper and related products, risks related to current global financial conditions, risks
related to current global financial conditions and the impact of COVID-19 on the Company’s business, uncertainties
inherent in the estimation of mineral resources, access and supply risks, risks related to the ability to access acid
supply on commercially reasonable terms, reliance on key personnel, operational risks inherent in the conduct of
mining activities, including the risk of accidents, labour disputes, increases in capital and operating costs and the
risk of delays or increased costs that might be encountered during the construction or mining process, regulatory
risks including the risk that permits may not be obtained in a timely fashion or at all, financing, capitalization and
liquidity risks, risks related to disputes concerning property titles and interests, environmental risks and the
additional risks identified in the “Risk Factors” section of the Company’s reports and filings with applicable Canadian
securities regulators.
Although the Company has attempted to identify important factors that could cause actual actions, events or results
to differ materially from those described in forward-looking information, there may be other factors that cause
actions, events or results not to be as anticipated, estimated or intended. Accordingly, readers should not place
undue reliance on forward-looking information. The forward-looking information is made as of the date of this news
release. Except as required by applicable securities laws, the Company does not undertake any obligation to
publicly update or revise any forward-looking information.