Metallurgy · 2015 campaign · operating record
A past producer with the receipts: metallurgy and the 2015 campaign
- Home
- Production & Metallurgy
Most “past producers” offer folklore. Charay offers mill records.
Clean, conventional metallurgy
- Bottle-roll cyanidation: 90–94% gold recovery at −60 and −100 mesh within 72 hours — amenable to agitated leaching.
- 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: oxide surface material 7.9–9.5 g/t Au / 120–127 g/t Ag; core composites 18.9–21.4 g/t Au / 110–125 g/t Ag — consistent with the drilling.
- Base metals in core composites (≈0.4–0.5% Cu, ≈0.7–0.8% Pb, ≈1.2–1.8% Zn) are modest; concentrate marketing in 2015 was routine.
The operating record
The 2015 campaign
The campaign ran as a 60:40 profit-share joint venture between Pafex and Minerales VANE, S.A. de C.V. — then a subsidiary of AIM-listed Rose Petroleum plc, the former VANE Minerals and the company that drilled the property in 2004–05 — with Minerales VANE as operator.
From the September 2014 signing, the mine was brought into production by 18 December 2014, reported to the market as on schedule and on budget — a statement about permits, surface access, logistics and workforce that no technical report can make for you. Ore was mined on a 2.2 m vein width, consistent with the drilled widths, and trucked to the operator’s San Dieguito de Arriba (SDA) mill at Acaponeta, Nayarit, at a forecast cash cost the operator disclosed as US$699 per gold-equivalent ounce.
| 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 grade per tonne milled | ≈7.4 g/t Au · ≈49.5 g/t Ag |
| Recovered ounces (troy) | 3,668 oz Au · 24,550 oz Ag |
What it proves
Three restart risks, already retired
Context worth pricing in: the campaign ran in a sub-US$1,200/oz gold environment, drawing heavily on near-surface oxide material — the lowest-grade part of the system — and still shipped concentrate profitably for ten months. The venture wound down in late 2015 as the operator’s UK parent completed its strategic pivot out of mining and into oil & gas — it sold its Mexican mill and mining subsidiary in 2017 and exited the country, all documented in its own market announcements. A corporate decision made an ocean away from Sinaloa; the orebody did what it was asked to do. At today’s metal prices, the identical physical output would gross a multiple of its 2015 revenue. The full project history →
The campaign proves that the deposit mines at its drilled widths, mills with conventional flowsheets, ships through existing regional infrastructure, and starts fast. For an acquirer, 2015 collapses the three risks that normally dominate a restart underwriting: metallurgical, logistical and social.
Ready to underwrite it?
Review the transaction framework, then request the operating records.