Element · Sn

Tin

A soft, low-melting metal whose main historical significance is that adding it to copper makes bronze.

Tin is a soft, silvery metal that melts at a temperature a good campfire can reach. On its own it is too weak to be structurally useful, and it has never been an important structural metal.

Its significance is almost entirely as an alloying element. A small proportion of tin transforms copper into bronze, and the scarcity and geographical concentration of tin ore is one of the reasons Bronze Age trade networks stretched as far as they did.

History

Tin deposits are far rarer and more localised than copper deposits. Cornwall, Iberia and Central Asia were the significant western sources, and the long-distance movement of tin is among the earliest evidence for organised international trade.

Uses

Solder is the largest use, and it changed shape rather than shrinking: lead-free solders required more tin, not less, so restricting lead raised tin consumption. Nearly all electronics are held together by tin alloy joints.

Tinplate — steel with a thin tin coating — is what a tin can actually is, the tin providing a non-toxic corrosion barrier over the steel that provides the strength. Tin chemicals stabilise PVC against heat and light, and tin remains the element that makes bronze bronze, the alloy that gave an age its name.

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 found in

Cassiterite — mineral Wikidata
Indium tin oxide — material · the dopant, at perhaps a tenth of the indium — it is what supplies the free electrons that make the film conduct Wikidata
Babbitt metal — alloy · 0–91% · the matrix of the tin-based grades, which are the ones modern specifications call for

is a component of

Bronze — alloy · 5–22% · the component that hardens the copper and lowers its melting point
Solder — alloy · 60–99% · the base of every solder in current use, leaded or not
Amalgam — alloy · 8–15% · in the dental alloy, controlling how fast the mixture sets
Pewter — alloy · 85–99% · almost all of it; the rest is there to stop it being too soft to hold a shape

is extracted from

Cassiterite — mineral · the only tin ore of economic importance Wikidata

is produced by

Smelting — process · reduced from cassiterite at relatively low temperature

is used as

Alloying — application · the addition that turns copper into bronze

is produced at

Cornwall — place · from antiquity until 1998

is an input to

Alloying and melting — process · the addition that hardens copper into bronze

is an alternative to

Lead — element · in solder: lead-free solders are tin-based, melt hotter, and were adopted under regulation rather than on performance

is used in

Smartphone — object · the solder on every joint on the board, and one of the four conflict minerals

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

Questions this page answers

Where it comes from, and what it becomes

Follow Tin 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

Tin → is produced by (reduced from cassiterite at relatively low temperature) → 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
Tin → is extracted from (the only tin ore of economic importance) → Cassiterite
Tin → is produced by (reduced from cassiterite at relatively low temperature) → Smelting → takes as input (roasted to drive off sulfur, then reduced to copper) → Chalcopyrite
Tin → is produced by (reduced from cassiterite at relatively low temperature) → Smelting → takes as input (reduced with carbon to metallic tin) → Cassiterite
Tin → is produced by (reduced from cassiterite at relatively low temperature) → Smelting → takes as input (reduced with coke in a blast furnace) → Hematite
Tin → is produced by (reduced from cassiterite at relatively low temperature) → Smelting → takes as input (the phosphate rock charged to the electric furnace, with coke to reduce it and silica to take up the calcium) → Apatite

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

Downstream — what it becomes

Tin → is an input to (the addition that hardens copper into bronze) → Alloying and melting → produces (tin into copper — the first alloy anybody made deliberately) → Bronze → is used to make (cast in a two-piece mould with a core, which is what bronze does better than the copper it replaced) → Bronze socketed axe → is associated with → Bronze Age complete chain
Tin → is a component of (the base of every solder in current use, leaded or not) → Solder → is used in (every joint on it, and tin-silver-copper since RoHS pushed the lead out from 2006) → Printed circuit board → is used in (and it is the change that made electronics manufacturable: assembly stopped being a wiring job and became a printing one) → Electronics manufacture → is associated with (and the supply chain it produced is the deepest and most concentrated in the world economy) → The semiconductor era complete chain
Tin → is a component of (the component that hardens the copper and lowers its melting point) → Bronze → is used to make (cast in a two-piece mould with a core, which is what bronze does better than the copper it replaced) → Bronze socketed axe → is associated with → Bronze Age complete chain
Tin → is used in (the solder on every joint on the board, and one of the four conflict minerals) → Smartphone → is used in (and it is where four separate raw-material arguments meet — the 3TG conflict minerals, cobalt, the rare earths, and everything too dispersed to recover) → Electronics manufacture → is associated with (and the supply chain it produced is the deepest and most concentrated in the world economy) → The semiconductor era complete chain
Tin → is a component of (almost all of it; the rest is there to stop it being too soft to hold a shape) → 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
Tin → is used as (the addition that turns copper into bronze) → Alloying

These are the most distinct paths onward. Tin ends up in others besides.