Stannum is a kind of silvery white and soft metal, it and lead, zinc is very similar, but look should a few brighter. Its hardness is lower, can dissection with the penknife it. It is had extend a gender goodly, be in especially temperature when 100 ℃ , can exhibit paper-thin tinfoil paper, ply is OK thin arrive under 0.04 millimeter.

Stannum also is the metal of a kind of low melting point, its melting point has 232 ℃ only, accordingly, want to use candle blaze to be able to fuse it into very good like mercuric and same fluidity liquid only.

Pure stannum has a kind of peculiar property: When stannic club and latten bend, can giving out a kind to as if particularly is to cry acoustical crepitation. This kind of sound is caused by the attrition that gives out between crystal. When crystal is out of shape, can produce such clash. Strange is, if change the alloy that uses stannum, when be out of shape, won't give out this kind of cry however. Accordingly, people often differentiates one gold nugget to belong to according to this one character of stannum is stannum after all.

One of main use of metallic stannum use production tin-plating iron sheet namely. The “ tin ” that stannic iron sheet often says with respect to people, this is a kind of plating stannic iron sheet. The stannic layer that fastens settle on face is very thin, but it is very useful “ appearance ” . Iron sheet put on this appearance, not only very beautiful, and acquired a lot of admirable property.

So, what good quality does the “ appearance ” that stannum makes have? Say simply, namely: Can fight corrode already, can gas defence again.

Why can tin-plating iron sheet have so good quality? This is not divided with stannic property. Original, stannic chemistry is very stable. It and water won't produce chemical reaction, although make it long-term be contacted with humid air, also can form a fine oxide film gradually in its surface only, this film can prevent stannic continuity combustion, this is tin-plating iron sheet fights corroded cause.

Additional, stannum and the action with acerbity inorganic very delay is overflowed, produce effect scarcely with organic acid, and stannic salt kind it is avirulent commonly, so, tin-plating iron sheet often is used to package data as food, for example food can box, biscuit box.