Lead

Lead and silver come out of the same rock. Galena is lead sulfide and it characteristically carries silver, so the two metals have always been mined together, and lead has spent most of its history as somebody else's byproduct. What makes the pair unusual is that the relationship inverted. In antiquity silver was the object and lead the residue left behind; by the twentieth century lead was the object — batteries, pipe, paint, petrol — and silver was what came up with it. No other pair of commodities on this list has swapped which of them is the product.

The date is the lead beads from Çatalhüyük at around 6500 BCE, with cupellation — the process that drives off the lead to recover the silver — from about 3000 BCE. That second date is when the pair becomes an industry rather than two materials. Lead itself is among the oldest smelted metals for straightforward reasons: its ore reduces easily at low temperature, and the metal is soft, workable, and melts at a heat any ancient hearth could reach.

It is also the clearest case on this list of a hazard identified early and then simply outweighed. Vitruvius advised earthenware pipe over lead on health grounds, and Nicander described the colic that lead produces; the toxicity was observed, written down, and ignored for two thousand years, because the metal was cheap, soft, corrosion-resistant and easy to work, and nothing else available did all four. The modern recognition of the late nineteenth century was not a discovery so much as a decision to act on something long known.

One use deserves separating out, because it made another commodity possible. Movable type was cast from lead alloy, and that is why the printing press was reproducible rather than a curiosity: type must be cast in quantity, to a consistent dimension, at a temperature a workshop can reach, and lead alloys are nearly the only material that satisfies all three. The press is usually credited to the press. A good deal of the credit belongs to the metal.

Its most consequential modern use was tetraethyl lead, and the arrangement that held it is already recorded in this corpus — General Motors, Standard Oil of New Jersey and DuPont jointly owning the patents through the Ethyl Gasoline Corporation and licensing the right to blend rather than selling the compound. What deserves recording alongside it is how the thing ended. UNEP's Partnership for Clean Fuels and Vehicles was formed in 2002, when 117 countries were still using leaded petrol; sub-Saharan Africa went unleaded in 2006; and in July 2021 the service stations of Algeria sold the last of it. UNEP's estimate of what the phase-out is worth annually is more than 1.2 million premature deaths avoided and some $2.45 trillion.

That ending is unique on this list and worth naming precisely. Leaded petrol is the only use of any commodity here that has been completely and globally eliminated — not restricted, not reduced, not substituted in rich countries while continuing elsewhere, but ended everywhere, verifiably, in a datable month. Asbestos, DDT, the chlorofluorocarbons, ivory and mercury are all under restriction with exemptions, residues, stockpiles or continuing illicit trade. This one is simply gone. It is a distinct way for a market to end, and it has exactly one instance.

And yet lead output has never been higher, which is the other half of the picture. World mine production was about 4.5 million tonnes in 2025, China alone accounting for 1.9 million, but total refined supply runs near twelve million tonnes because roughly two-thirds of it is now recycled; in the United States secondary lead equals about seventy percent of apparent consumption and lead-acid batteries take some sixty-seven percent of it. The commodity whose most notorious application was abolished is produced in greater quantity than ever, circulating in a closed loop of the same metal through successive batteries. The harm has moved with it: informal battery breaking in low-income countries is now among the largest sources of lead exposure anywhere, which is the familiar pattern of a hazard relocating to wherever regulation is thinnest rather than ceasing. On boundaries, galena as ore is here, and an entry about a lead-silver ore body carries silver alongside, as this corpus's entries already do. Lead-acid batteries are electrical equipment and the lead within them is here. Tetraethyl lead and the lead compounds sold as reagents are industrial chemicals; white lead and red lead as pigments are colorants; lead cast as shot or ball is a weapon. Lead in solder is here with tin alongside, by the alloy rule set at tin. Type metal is here, and what is printed with it is papyrus, parchment, and paper, or news. The date is c. 6500 BCE, on the Çatalhüyük lead beads.