How tin is made
Bend a bar of tin by hand and you can hear it crackle, a sound called tin cry.
- stations
- 5
- things upstream
- 3
- raw sources
- 2
- steps from the ground
- 2
The short version
Tin comes from cassiterite, a heavy tin oxide, and about 80 percent of it is recovered from sand and gravel deposits downstream of the original rock. Dredges and washing plants separate the heavy grains. Furnaces then reduce the oxide with carbon or coke to molten tin, which is cast into ingots.
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Dredge the tin sands
Cassiterite is hard, heavy and chemically tough, so it washes out of eroded rock and settles in river valleys and under the sea. Dredging, hydraulicking and open pits are the cheapest ways to dig it.
Goes in -
Crush hard-rock ore
Ore from the original veins is broken up so that the grains of tin oxide are freed from the rock around them.
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Sort the heavy grains
Tin dioxide has a high specific gravity. Washing lets the heavy grains sink while lighter waste is carried away, leaving a concentrate rich in cassiterite.
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Reduce it with carbon
Carbon or coke heats the concentrate in a reverberatory or electric furnace. Carbon takes the oxygen from the tin oxide and leaves liquid tin.
Goes in -
Cast into ingots
Molten tin is poured into molds. It melts at only about 232 °C, which is the reason it is so easy to alloy and to cast.
Worth repeating
- Just under half of the world's tin was used in solder in 2018.
- Below 13.2 °C, white tin can slowly turn into a brittle gray form.
- The United States has not mined tin since 1993, yet it recycled nearly 14,000 tonnes in 2006.
Back to the ground
Follow every input upstream and tin starts as these 2 raw sources.
Where it comes from
2011, tonnes of tin mined.
Where it goes next
Tin feeds 11 lines directly and reaches 138 things in total.
Further down the line
Keep walking
Sources
Cite this page: "How tin is made." Assembly Line, 2026-11-03. https://assemblyline.org/make/tin