Tin (symbol Sn) is a silvery-white, lustrous gray metallic element. Tin is soft, pliable and has a highly crystalline structure. When a tin bar is bent or broken, a crackling sound called a "tin cry" is produced due to the breaking of the tin crystals. People have been using tin for at least 5,500 years. Tin has been found in the tombs of ancient Egyptians. In ancient times, tin and lead were considered different forms of the same metal. Tin was exported to Europe in large quantities from Cornwall, England, during the Roman period, from approximately 2100 BC to 1500 BC. Cornwall was one of the world's leading sources of tin for much of its known history and into the late 1800s.
The principal ore of tin is the mineral cassiterite, which is found in Malaya, Bolivia, Indonesia, Thailand, and Nigeria. About 80% of the world's tin deposits occur in unconsolidated placer deposits in riverbeds and valleys, or on the sea floor, with only about 20% occurring as primary hard-rock lodes. Tin deposits are generally small and are almost always found closely allied to the granite from which it originates. Tin is also recovered as a by-product of mining tungsten, tantalum, and lead. After extraction, tin ore is ground and washed to remove impurities, roasted to oxidize the sulfides of iron and copper, washed a second time, and then reduced by carbon in a reverberatory furnace. Electrolysis may also be used to purify tin.
Pure tin, rarely used by itself, was used as currency in the form of tin blocks and was considered legal tender for taxes in Phuket, Thailand, until 1932. Tin is used in the manufacture of coatings for steel containers used to preserve food and beverages. Tin is also used in solder alloys, electroplating, ceramics, and in plastic. The world's major tin research and development laboratory, ITRI Ltd, is funded by companies that produce and consume tin. The focus of the research efforts have been on possible new uses for tin that would take advantage of tin's relative non-toxicity to replace other metals in various products. Some of the replacements could be lead-free solders, antimony-free flame-retardant chemicals, and lead-free shotgun pellets. No tin is currently mined in the U.S.
Tin futures and options trade on the London Metal Exchange (LME). Tin has traded on the LME since 1877 and the standard tin contract began in 1912. The futures contract calls for the delivery of 5 metric tons of tin ingots of at least 99.85% purity. The contract trades in terms of U.S. dollars per metric ton.
Prices - The average monthly price of tin (straights) in New York in 2007 rose by +61.1% yr/yr to a record high of $9.15 per pound. The 2007 price of $9.15 is more than triple the 3-decade low of $2.83 per pound seen as recently as 2002. The average monthly price of ex-dock tin in New York in 2007 rose by +62.7% yr/yr to $6.79 per pound, and that is more than triple the 3-decade low of $1.99 per pound posted in 2002.
Supply - World mine production of tin in 2005 (latest data available) fell by 2.0% yr/yr to 292,000 metric tons, down from last year's record high of 298,000 metric tons. The world's largest mine producers of tin are China with 41% of world production in 2005, Indonesia with 27%, and Peru with 14%. World smelter production of tin rose +13.3% in 2005 to 350,000 metric tons, which is a new record high. The world's largest producers of smelted tin are China with 35% of world production in 2005, Indonesia with 19%, and Malaysia with 11%. The U.S. does not mine tin, and therefore supply consists only of scrap and imports. U.S. tin recovery in 2006 fell -11.2% to 6,810 metric tons, which was a new record low.
Demand - U.S. consumption of tin (pig) in 2007 (through April) fell -2.5% to an annualized 41,067 metric tons, which is a new record low. The breakdown of U.S. consumption of tin by finished products in 2005 shows that the largest consuming industry of tin is solder (with 40% of consumption), followed by chemicals (20%), tin plate (18%), and bronze and brass (8%).
Trade - The U.S. relied on imports for 79% of its tin consumption in 2007. U.S. imports of unwrought tin metal in 2005 fell 21.2% to 37,500 metric tons, not much above the 9-year low of 37,100 metric tons in 2003. The largest sources of U.S. imports in 2005 were Bolivia (14% of total imports), Indonesia (14%), China (12%), and Brazil (6%). U.S. exports of tin in 2005 rose +18.6% yr/yr to 4,330 metric tons.