Element · Sb

Antimony

A metalloid that expands as it solidifies, which is why printing type was made from it.

Antimony is one of the few substances that expands on freezing. Alloyed with lead and tin it produces a metal that fills a mould completely as it sets, capturing fine detail — which is exactly what movable type requires. Type metal was essentially this alloy for four centuries.

Its modern use is dominated by flame retardants, where antimony trioxide works alongside halogenated compounds, and by lead-acid battery grids.

Uses

Antimony's principal use is as a flame retardant. Antimony trioxide is not a retardant on its own but sharply improves halogenated ones, and it is present in a great deal of plastic, textile and cable insulation for that reason.

It also hardens lead: lead-antimony alloy is what makes car battery grids and lead shot rigid enough to be useful. Historically it was the metal that made movable type possible, because antimony expands slightly on freezing and fills a mould's detail rather than shrinking from it.

Medium confidence Weak evidence

How we know: checked recently · only one source, so there is nothing to cross-check it against · stated directly by the source.

How this connects

Where a connection has been confirmed by an outside reference, that reference is named beside it.

is used as

Alloying — application · hardens lead, and expands on freezing to fill a mould completely
Flame retardancy — application · antimony's principal use, generally alongside a brominated compound

is extracted from

Stibnite — mineral · essentially the only ore of antimony Wikidata

is produced by

Smelting — process · reduced from the oxide left by roasting stibnite

is sourced from

Lead — element · partly from lead ores, though antimony differs from the rest of this list in also being mined for itself from stibnite

is a component of

Pewter — alloy · 0–8% · the principal hardener in modern pewter

is found in

Babbitt metal — alloy · 4–15% · forms the hard cuboid crystals that carry the load in the soft matrix
Stibnite — mineral Wikidata

Sources

Material World
Our own writing
Wikidata
Wikimedia Foundation · Creative Commons CC0 1.0 Universal (public domain dedication)
PubChem
US National Library of Medicine · Mixed — aggregated third-party content, rights retained by depositors
NIST — National Institute of Standards and Technology
United States Department of Commerce · US Government work — public information, credit requested

Where it comes from, and what it becomes

Follow Antimony back to what it starts as, and forward into what it becomes. Each step is a documented one — a real route material takes, not a chain of inference.

Upstream — what it comes from

Antimony → is produced by (reduced from the oxide left by roasting stibnite) → Smelting → takes as input (as the element removed, not added) → Oxygen → is produced by (the largest output by tonnage, and the reason air separation units sit beside steelworks) → Air separation → takes as input (the feedstock, and an unusual one in being free, unlimited and available anywhere — the cost is entirely the energy to liquefy it) → Air
Antimony → is sourced from (partly from lead ores, though antimony differs from the rest of this list in also being mined for itself from stibnite) → Lead → is produced by (as the oxide, from galena, by the same route) → Roasting → takes as input (a copper sulfide; roasting drives off the sulfur that would otherwise prevent reduction) → Chalcopyrite
Antimony → is extracted from (essentially the only ore of antimony) → Stibnite
Antimony → is produced by (reduced from the oxide left by roasting stibnite) → Smelting → takes as input (roasted to drive off sulfur, then reduced to copper) → Chalcopyrite
Antimony → is produced by (reduced from the oxide left by roasting stibnite) → Smelting → takes as input (reduced with carbon to metallic tin) → Cassiterite
Antimony → is produced by (reduced from the oxide left by roasting stibnite) → Smelting → takes as input (reduced with coke in a blast furnace) → Hematite

These are the most distinct paths back. Antimony can be traced through others besides.

Downstream — what it becomes

Antimony → is a component of (the principal hardener in modern pewter) → Pewter → is used as (the reason it existed: cast cheaply on a domestic hearth, cleanable, and recastable when it dented — the tableware of ordinary European households for five centuries) → Tableware and vessels
Antimony → is used as (hardens lead, and expands on freezing to fill a mould completely) → Alloying
Antimony → is used as (antimony's principal use, generally alongside a brominated compound) → Flame retardancy