Arizona Gold’s Philadelphia project: underground vs open-pit lens for mine planners
Reviewed by Joe Ashwell

First reported on MINING.com
30 Second Briefing
Arizona Gold & Silver’s latest drilling at the Philadelphia project in Arizona has cut broad gold-silver mineralisation beneath the Red Hills target, including hole PC26-173 with 7 metres at 4.24 g/t gold and 15.2 g/t silver from 456 metres within 44 metres at 1.48 g/t gold and 7.2 g/t silver from about 446 metres. Hole PC26-172 returned 70 metres at 1.16 g/t gold and 5.6 g/t silver from 417 metres, including 10 metres at 3.27 g/t gold and 19.3 g/t silver from 459 metres, extending mineralisation down-dip in the Perry zone. The company is modelling a north-plunging higher-grade shoot within a 3‑km Arabian Fault corridor to evaluate both underground and bulk-tonnage open-pit scenarios.
Technical Brief
- Hole PC26-173’s broader 44 m interval includes 22 m at 2.52 g/t Au from 447 m.
- The same hole also contains 13 m at 3.51 g/t Au from 456 m depth.
- Philadelphia lies ~320 km northwest of Phoenix in the historic Oatman high-grade vein district.
- Oatman district has historically produced >2.5 million oz Au from underground vein operations.
- Arizona Gold & Silver has advanced Philadelphia since 2019, initially drilling from the property’s north end.
- Acquisition of patented claims in 2021 enabled discovery of the Perry vein and associated stockwork zone.
- Hole PC26-174 was drilled directly beneath PC26-173; assays are pending to constrain down-dip continuity.
- Ongoing hole PC26-175 is collared ~60 m north of PC26-173 to test the revised high-grade shoot projection.
- Drilling is also targeting a broad geophysical anomaly beneath Red Hills to link Perry Zone geometry and bulk-tonnage potential.
- Market reaction was negative: AZS fell 13% to C$0.58, implying ~C$88 million market capitalisation.
Our Take
The combination of multi‑tens‑of‑metres gold intervals at depths beyond 400 m at the Philadelphia project and a modest Arizona Gold & Silver market cap of about C$88 million suggests that any move towards an initial resource could materially re-rate the company relative to other single‑asset juniors in our database.
The 3 km Arabian Fault corridor at the Philadelphia property, in a district with historical production of 2.5 million oz of gold, implies scope for multiple shoot discoveries, which for practitioners means structural and vein continuity modelling will likely be as critical as simple step‑out drilling density in future programmes.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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