Operating record · metallurgy
A past producer with the receipts: metallurgy and the 2015 campaign
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Most “past producers” offer folklore. Charay offers mill records.
Metallurgy
Clean, conventional metallurgy
Independent test work confirms the ore behaves the way its mineralogy suggests it should. Bottle-roll cyanidation returns 90–94% gold recovery at −60 and −100 mesh within 72 hours — amenable to agitated leaching — and flotation at commercial scale produced concentrates grading ≈290 g/t Au and ≈1,940 g/t Ag during the 2015 campaign.
Metallics assays match standard fire assays: no coarse-gold nugget effect, so grade control behaves. Head-grade verification on bulk samples ran 7.9–9.5 g/t Au / 120–127 g/t Ag in oxide surface material and 18.9–21.4 g/t Au / 110–125 g/t Ag in core composites — consistent with the drilling. Base metals (≈0.4–0.5% Cu, ≈0.7–0.8% Pb, ≈1.2–1.8% Zn) are modest; concentrate marketing in 2015 was routine.
| Gold recovery | 90–94%, 72-hr bottle-roll cyanidation |
|---|---|
| Grind | −60 and −100 mesh tested |
| Flotation | Commercial scale, 2015 — conc. ≈290 g/t Au · ≈1,940 g/t Ag |
| Nugget effect | None — metallics match fire assays |
| Head grades | Oxide 7.9–9.5 g/t Au; core composites 18.9–21.4 g/t Au |
| Base metals | Modest Cu–Pb–Zn; routine concentrate terms |
The 2015 operating campaign
From signature to first ore in under four months
Under a production joint venture executed in September 2014, first ore was delivered that December — on schedule and budget — and the mine ran through 2015, with ore treated at a nearby toll flotation mill. Average mined width was 2.2 m on a 1.0–2.0 m vein.
| 2015 campaign | Result |
|---|---|
| Ore mined and processed | 15,430 t (Mar–Aug 2015) |
| Concentrate shipped | 393 dmt (Feb–Dec 2015, 14 shipments) |
| Average concentrate grade | ≈288 g/t Au · ≈1,967 g/t Ag |
| Contained metal | 114.1 kg Au · 763.6 kg Ag |
| Recovered ounces (troy) | 3,668 oz Au · 24,550 oz Ag |
| Recovered grade per tonne milled | ≈7.4 g/t Au · ≈49.5 g/t Ag |
Context worth pricing in
The hard year, survived profitably
The campaign ran in a sub-US$1,200/oz gold environment, drew heavily on near-surface oxide material — the lowest-grade part of the system — and still shipped concentrate for ten months. The operator’s published restart planning had forecast cash costs of US$699/oz AuEq. The joint venture concluded in 2017 when the operator exited Mexico for portfolio reasons unrelated to the geology; the orebody did what it was asked to do.
The operator’s 2014 re-evaluation — 29,000 oz Au and 173,000 oz Ag in 90,000 t — is a historical estimate prepared before, and not compliant with, NI 43-101 or S-K 1300; a Qualified Person has not done sufficient work to classify it as a current mineral resource, and it should not be relied upon. It is presented as part of the documented record, alongside the mill data above.
The grades that fed the mill are still in the ground.
Everything mined to date sits above 35 m, in a system drilled to only 50 m and open below.