Silver — Nobody’s Main Business, Everybody’s Input
Roughly three-quarters of the world’s silver is produced by mines that are not looking for silver. That single fact breaks the normal economics of the metal.
Ore to Vehicle · Part 2 — The Metals · Chapter 4 · 14 min read
Roughly three-quarters of the world’s silver is produced by mines that are not looking for silver. It comes out alongside lead, zinc, copper and gold, and that single fact breaks the normal economics of the metal.
~73 %
Byproduct share of supply
~25,000 t
Annual mine supply
25–50 g
Per vehicle
Bronze Age
Age of the cupellation step
4.1 — Where silver actually comes from
KGHM in Poland is one of the world’s largest silver producers and is a copper company. Mexico, Peru and China lead; Chile and Poland follow.
4.2 — Supply that ignores price
In plain English
If the silver price doubles, a lead-zinc mine does not mine more, because its economics are set by lead and zinc. Only about a quarter of supply comes from primary silver mines that respond to the silver price at all.
Supply is largely price-inelastic, so demand shocks resolve through price and inventory rather than through new production — the opposite of how most commodity markets are taught.
4.3 — The technical route — out of copper’s anode slime
- •1 · Anode slime collection. Copper electrorefining leaves 2–10 kg of slime per tonne of copper, containing Ag, Au, Pt, Pd, Se, Te and Cu.
- •2 · Decopperising leach. Slime leached with H₂SO₄ and air to remove residual copper.
- •3 · Selenium removal. Ag₂Se + O₂ → 2 Ag + SeO₂↑. Selenium volatilises and is captured; it is itself a valuable byproduct.
- •4 · Smelting to doré. Residue smelted to a doré bar — a rough Ag-Au alloy, typically 90–95 % silver.
- •5 · Electrolytic refining. Moebius or Thum Balbach cell, AgNO₃/HNO₃ electrolyte → 99.9–99.99 % silver crystal. Gold does not dissolve and drops out as slime — again.
4.3.1 — The older route, from lead
From lead smelting the route is different and older: the Parkes process adds zinc to molten lead, silver preferentially dissolves into the zinc, the zinc-silver crust is skimmed and the zinc distilled off. What remains is refined by cupellation — oxidising the lead away in a porous vessel, a technique in continuous use since the Bronze Age.
4.4 — Where it goes in a vehicle
Important
Only 25 to 50 grams per car, but in places with no substitute: sintered silver die-attach under SiC power modules, where silver’s thermal conductivity and its ability to sinter below its melting point make it the only practical bond for a device that cycles hard and runs hot. Plus relay and connector contacts, and conductive pastes.
The larger story is next door. Solar cell metallisation consumes a large and growing share of world silver, and it competes for the same metal — against a supply that, as established above, does not answer the price.
Quick check: test yourself
1.A shortage develops in silver. How does the market clear it?
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2.Why is sintered silver used under SiC power modules rather than solder?
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3.Where does silver appear in the copper chain, and where does it not?
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Chapter summary
- ✓Roughly 73 per cent of silver is produced by mines seeking another metal, so supply is largely price-inelastic.
- ✓The main modern route is out of copper anode slime; the older lead route uses the Parkes process and cupellation, which dates to the Bronze Age.
- ✓A vehicle contains only 25 to 50 grams, but the sintered die-attach under SiC modules has no substitute.
- ✓Solar metallisation competes for the same metal against a supply that does not answer price signals.
Frequently asked questions
Why does the silver price not bring new silver supply?+
Because roughly 73 per cent of world silver is produced by mines whose economics are set by another metal entirely — lead, zinc, copper or gold. If the silver price doubles, a lead-zinc mine does not mine more. Only about a quarter of supply comes from primary silver mines that respond to the silver price at all, so supply is largely price-inelastic and demand shocks clear through price and inventory instead.
How is silver actually extracted?+
Most commonly out of copper anode slime: the slime is leached to remove residual copper, roasted to volatilise selenium as SeO₂, smelted to a doré bar of 90 to 95 per cent silver, then electrolytically refined in a Moebius or Thum Balbach cell with a silver nitrate electrolyte to 99.9 to 99.99 per cent — with gold dropping out as slime again. From lead smelting the route is older: the Parkes process adds zinc to molten lead, silver preferentially dissolves into the zinc, the crust is skimmed and the zinc distilled off, and cupellation oxidises the remaining lead away.
What is silver doing in an electric vehicle?+
Only 25 to 50 grams, but in places with no substitute. The critical one is sintered silver die-attach under SiC power modules, where silver’s thermal conductivity and its ability to sinter below its melting point make it the only practical bond for a device that cycles hard and runs hot. Plus relay and connector contacts and conductive pastes. The larger competition is next door: solar cell metallisation consumes a large and growing share of world silver.
Reviewed by
Ore to Vehicle is an original educational series on the battery and EV materials supply chain. Country shares, grades, prices and policy status are approximate, drawn from public reporting as of mid-2026, and move year to year — treat them as orders of magnitude rather than as a ledger, and verify before relying on them commercially.