Tin is a chemical element with the symbol Sn from the Latin word “stannum. ” Its atomic number is 50 and its atomic mass is 118. 71. Tin is classified in the ‘Other Metals’ section which can be located in groups 13, 14, and 15 of the Periodic Table. All of these elements are solid, have a relatively high density and are opaque. This silvery, ductile metal is not easily oxidized in air and resists corrosion. Tin is usually malleable, but when cooled it is very brittle. It is found in many alloys and is used to coat other metals.
It can be alloyed with copper to make bronze. Pewter alloys contain about 85% to 99% tin. Tin is obtained from the mineral ore cassiterite, where it occurs as an oxide. It is extracted by roasting cassiterite in a furnace with carbon. Tin makes up only about 0. 001% of the earth’s crust and is chiefly mined in Malaysia and found in Bolivia, Indonesia, Thailand, and Nigeria. Tin was discovered by the ancients nearly 5500 years ago and was mentioned in the Old Testament. It is one of the earliest metals known and they think it was first mined in South-East England.
Because of its hardening effect on copper, tin was used in bronze implements as early as 3,500 BC. Tin is used in industries to form many useful alloys and as a coating for steel cans. Tin cans contain a thin coating of tin to inhibit rust. The small amount of tin found in canned foods is quite harmless. Tin used to be used to make tin foil, but it is now exclusively made of aluminum. The agreed limit of tin content in U. S. foods is 300 mg/kg. The trialkyl and triaryl tin compounds must be handled carefully.
Alloys of tin are very important including: soft solder, type metal, fusible metal, pewter, bronze, bell metal, Babbitt metal, White metal, die casting alloy, and phosphor bronze. Tin is the perfect metal for casting toy soldiers. It melts at a fairly low temperature, so you can use simple molds, even molds made of special rubber. It is non-toxic, unlike lead and it is also shiny and doesn’t tarnish. It is also the perfect metal for casting toy soldiers because it is inexpensive. Tins price over the past 25 years has varied from 50 cents/lb to its present price of about $4/lb. as of January 1990.
Tin is used in the Pilkington process to produce the glass for windows. In the Pilkington process, molten glass is poured into a pool of molten tin. The glass floats on the surface of the tin and cools, this forms solid glass with a flat even surface. Most of the window glass produced today is produced this way. Tin salts are sometimes sprayed onto glass to make an electrically conductive coating. These can then be used to make frost-free windshields. Overall, the element tin is commonly used in many industries and used for household items and for coatings on many items like cooking pans and soda (tin) cans.
Tin cans have a very thin layer of tin so it is usually not harmful, but tin can cause skin and eye irritations, liver damage, loss of red blood cells, brain damage and a few other health issues. Although we don’t know who discovered tin scientists think someone had built a fire and they discovered that the fire had changed the rocks and some metal had formed. It was an accidental discovery. And it happened at different times at different places around 5500 years ago. Tin is also used to form many useful alloys that contribute to the industrial word and without tin we wouldn’t be as advanced in technology as we are today.