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Old 02-08-2006, 06:31 PM
yabob yabob is online now
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Originally Posted by ultrafilter
Seriously, the property you're looking for is density. Otherwise, you could just use a lot of aluminum to get the weight you need. As far as I know, lead is the densest commonly occurring metal.
Probably correct, depending on what you mean by "commonly occurring". The densest metallic element is osmium or iridium depending on which source you read (they are very close at any rate). They are about twice the density of lead, and you could probably obtain some if you wanted to. The problem is that osmium and iridium are precious metals, and a quick check shows that iridium is cheaper currently, only about $200 per troy ounce. Tungsten is very nearly as dense (about the same density as gold), and probably cheaper, since it's an industrial, not precious, metal. Some densities:

Osmium - 22.61 g/cm
Iridium - 22.65 g/cm
Platinum - 21.45 g/cm
Gold - 19.3 g/cm
Tungsten - 19.25 g/cm
Lead - 11.34 g/cm
Mercury - 13.534 g/cm
Silver - 10.49 g/cm

The trouble with tungsten from your point of view is that it's going to be very difficult to work with. It's noted for it's extremely high melting point (3422 C, 6192 F), it's incredibly difficult to machine, and very hard.