Lead Concentrate Specs for Smelters: What We Can Ship from Gilgit-Baltistan

A smelter buyer in Tianjin asked me last month what our typical Pb assay looked like, and whether we could hold under 0.3% arsenic on a sustained tonnage basis. Fair question. That's the conversation I want to have — not the marketing one.

So here's a straight technical note on what we can actually ship, what the penalty elements look like, and where the trade-offs sit. If you run a smelter or trade concentrates, this is written for you.

What our lead concentrate typically looks like

The galena-bearing zones we're working sit within carbonate-hosted and vein-type systems across two of our concessions in Gilgit-Baltistan. Mineralogy is dominantly galena with subordinate sphalerite, minor pyrite, and trace tetrahedrite in one of the vein systems. That last one matters — I'll come back to it.

On flotation testwork and current pilot batches, typical concentrate assays we're delivering:

• Pb: 62–68% (target 65% for standard contracts)
• Ag: 180–420 g/t depending on the zone (the tetrahedrite-bearing vein carries the higher silver)
• Zn: 1.8–3.5% (co-recovery is possible but we're running a Pb-only circuit right now)
• Fe: 2.1–4.4%
• SiO₂: 1.5–3%
• Moisture at load port: 7–8% typical, we can dry to 6%

Penalty elements — because this is what actually decides whether a smelter picks up your material:

• As: 0.08–0.24% on the carbonate-hosted material. The vein material with tetrahedrite runs higher, 0.35–0.6%, and we blend or sell separately.
• Sb: 0.05–0.12% clean zones, up to 0.9% in the tetrahedrite zone
• Bi: under 0.05%
• Hg: under 10 ppm across everything we've assayed so far, which is one of the cleaner aspects of this district
• Cd: trace, well under smelter thresholds
• Cl and F: not an issue, we're not near evaporite sequences

Honestly, I got the arsenic question wrong the first year. I assumed we could market the whole flowsheet as one product. We couldn't. The tetrahedrite-influenced material needed to be kept as a separate stockpile and sold to smelters that could take the As/Sb load (usually with a discount and sometimes as a silver-rich byproduct feed). Lesson learned. Now we split at the mine.

Volumes, packaging and logistics from Pakistan

Here's where a lot of overseas buyers get frustrated with pakistan lead mining export deals — someone quotes them 50,000 tonnes a year and then ships 800 tonnes and goes quiet. I'd rather tell you what's real.

Current sustainable output from our two active Pb concessions combined: 1,800–2,400 tonnes of concentrate per month, ramping. We can commit to 24,000 tpa on a firm offtake with a six-month ramp. Beyond that, we'd need JV capital to expand the mill — which is exactly the conversation we're open to.

Road haulage runs from the mine sites down the Karakoram Highway to Islamabad, then onward by container or bulk truck to Karachi Port or Port Qasim. Total road distance is roughly 1,650 km from the northern concession. Transit time is 5–7 days depending on the season. Winter (December through March) the KKH can close for days at a time around the higher passes — buyers need to build that into shipping schedules. We do.

Packaging: 1.0–1.1 tonne bulk bags, double-lined UV-treated polypropylene, loaded into 20-foot containers at roughly 26 tonnes per box. Bulk vessel shipment is possible for offtakes above 5,000 tonnes per shipment but honestly, containerised is cleaner for lead concentrate given the moisture and dust rules at Karachi.

Documentation we provide as standard:

• SGS or Intertek assay at load port (buyer nominates)
• Moisture certificate
• Certificate of Origin (Pakistan)
• IMSBC-compliant declaration (UN 3077, Group A/B depending on moisture)
• Radiation clearance certificate — some Chinese and Japanese ports now insist on this
• Kimberley-style chain of custody documents if the buyer requests, though it's not required for Pb

Contract terms we actually sign

Most of our current contracts are structured on LME Pb cash settlement average over the quotational period, with:

• Payable Pb: 95% subject to minimum deduction of 3 units
• Payable Ag: 95% above 30 g/t, at LBMA silver fix average
• Treatment charge: negotiated, currently in the $180–220/dmt range depending on spot market
• Penalties: standard smelter schedules for As, Sb, Bi above thresholds
• Payment: 90% provisional on B/L against LC, final on umpire assay

We've done CIF China, CIF Busan, and FOB Karachi. FOB is simpler for us and most experienced traders prefer it anyway.

One thing I'll say plainly. If you're evaluating a lead concentrate supplier from Pakistan and the counterparty won't share prior assay history, won't name their SGS reference numbers, and won't let you visit the mine — walk away. There are serious operators here and there are brokers three layers removed from any actual rock. The GB mineral title system is public record on the concession side; ask for the lease number and verify it with the Gilgit-Baltistan Mines and Minerals Department. Takes a week. Worth it.

What I'd want to know if I were on your side of the table: can we send an inspector to the mine and the mill, take splits from three separate lots, run them through an independent lab, and compare to what we've been told? Yes. We host that visit at our cost for any buyer serious about a 12-month-plus offtake. Bring your own metallurgist if you want. Most do.

If you're sizing a smelter feed book for 2025 and 2026 and want a clean galena-dominant Pb concentrate with meaningful silver credits and manageable penalties, drop me a line with your typical spec sheet and target tonnage. I'll come back with what we can commit to and what we can't — in that order.