TIN (AS. tin, 011G. zin, Ger. Zinn, tin; con nected with Goth. tains, AS. tan, ORG. zero, twig, thin leaf of metal). A metallic element known since ancient times. Implements formed of an alloy of tin and copper have been found among ancient Assyrian remains. and the tin employed in the manufacture of such bronze was obtained by the Phoenicians from the islands called Cassiterides. somewhere MT the west coast of Europe. It is known definitely that after the conquest of Britain by the Romans till was carried from the Cornish mines through Gaul, by way of Marseilles, to Italy. Pliny distinguished tin as plum bunt al bunt or candid/ant from plumbunt nigrunt (lead), and about the fourth century the name of stan was given to tin. The alchemists called it jupiicr, and sometimes diaboltis inctalla•una, owing to its property of forming brittle alloys. Native tin is said to have been found in small crystalline grains with corundum, gold, and platinum in superficial deposits in New South Wales, and it has been reported elsewhere, hut it is extremely doubtful whether the metal occurs native. The principal ore is the dioxide, cassit erite, sometimes called 'tinstone;' tin is also found as the sulphide, with copper and zinc, the mineral being known as stannite or tin pyrites. Smaller quantities of tin are also con tained in certain other minerals.
Tin (symbol, Sn, stannum; atomic weight, 119.05) is a silver-white, lustrous metal that has a specific gravity of about 7.3, and melts at 235° C. (455° F.). It can be easily rolled or hammered out to thin foil, and at 100° C. (212° F.) may be drawn into wire, which, however, pos sesses but little tenacity. Tin has a fibrous structure, and when bent emits a peculiar crack ling sound. caused by the friction of the crystal
line particles. It finds extensive use in the manufacture of tin plate (see below), in the preparation of vessels for household and techni cal purposes, for the manufacture of tin-foil, for tinning copper and iron, and in the manufacture of alloys, including amalgam for silvering mir rors, hell metal, bronze, gun metal, pewter, type metal, etc. It combines with oxygen to form two oxides, of which the stannous oxide, or monoxide, is an olive brown powder that is obtained when stannous oxalate is heated out of contact with air, and combines with basic radicles to form stannates, of which the sodium stanuate is used in calico dyeing and printing. The stannic oxide, or dioxide, which is found native as cassiterile, is obtained as a white powder when tin is heated until it burns in the air. It finds some use, under the name of 'putty powder,' for polishing plate glass, and also for imparting a white color to glass and enamels. .Stannous chloride, SnC1,, and stannic chloride, SnCL, are both used as mordants in dyeing and calico printing under the name of 'tin salts' or 'tin crystals,' and are readily prepared by dissolving the metal in hydrochloric acid. Stannic sulphide, which is prepared by heating tin with mercury, sulphur, and ammonium chloride, is known commercially as `mosaic gold,' and was formerly used for gild ing, imitating bronze. etc. The beautiful purple colored precipitate obtained by the reaction of gold chloride on stannous salts has been described under CAssms, PURPLE OF (q.v.).