|Aluminum-scandium master alloy.
This irregular lump comes from Tim Worstall, the world's leading expert on the scandium trade by virtue of the fact that he is a good fraction of the world's scandium traders. Virtually no pure scandium metal is sold in the world, most of the scandium that trades hands is either scandium oxide, or master alloys like this. A master alloy is a precisely formulated mixture of metals that is meant to be added to a pot of more common metal to form the desired final alloy. This one is aluminum with about 2% scandium added. Why not just buy pure scandium and add it to a pot of aluminum? After all, that would save a lot of weight shipping around 98 pounds of aluminum for every two pounds of scandium. But creating alloys from pure metals is not always so easy. For one thing, the melting point of scandium is much, much higher than that of aluminum: You'd have to heat your aluminum much higher than otherwise necessary in order to get it to absorb the scandium. By purchasing scandium pre-dissolved in aluminum, the end user can simply dump the master alloy chunks into their pot of aluminum near its normal melting point.
Aluminum-scandium alloys are used for things like very expensive bicycle frames, baseball bats, and even a line of light-weight handguns. (Amazingly, two separate readers have written in to me about this last application, both commenting that the guns are very uncomfortable to shoot because the light weight results in a strong kickback.) Tim is excited by the possibilities for expanded use of these alloys, including in things like aircraft wings.
Source: Tim Worstall
Contributor: Tim Worstall
Acquired: 19 January, 2004