Cool fact, the "tin cry" (also exhibited by zinc, and I've sometimes had mild steel maybe do it, but maybe that was due to oxides or other impurities Idunno?) is due to shockwaves as the crystals deform -- IIRC, something about, the crystals have relatively few slippage planes and relatively high binding force, but not so much that they fail instantly in brittle fracture; the effect is, when a plane does slip, it goes off explosively, faster than the speed of sound in the material. Hence the crystal slips all at once, and you hear a tic. A cacophony of these going off at once, and you get some angry hissing sound, a "cry".
Zinc is hexagonal, and tin tetragonal, while most other metals are fcc or bcc cubic.
So also, they tend to be less malleable or ductile -- though clearly, not so much that they can't be shaped about easily as any other metal or alloy. Not that zinc sheet or wire has much use, but tin foil and sheet were handy back in the day, and tin wire, well that's also known as solder.
(I forget what all the whole story about this is, or how much I might be leaving out -- things like induced twinning, or creep, which relieve stress, increasing plasticity despite the above facts. Although, I'm pretty sure it's not creep -- which however is very much a property of lead, which makes it very easy indeed to form into sheet/wire, and is part of why leaded solder is relatively soft, and well, creeps under load, which you've seen if you ever left some solder hanging partially off the bench.)
Tim
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