One slight correction. The germanium doesn't replace the copper
entirely. It is an addition to the alloy in small amounts. The way
it works is that it oxidizes preferentially over the silver and
copper and since it is a transparent type of oxide it give the
appearance of being tarnish resistant. It is a nice alloy but does
have some different properties you have to be aware of. The color
spectrum is different when you heat it so you have to adjust your
soldering technique if you go by eye to tell when the right amount of
heat is applied. It also apparently laser welds better than regular
sterling. We use it on some of our hollowware items and the response
has been positive as it really reduces the amount of fire scale
during annealing operations.
Metallurgist, Technical Manager
Tiffany & Co.
300 Maple Ridge Drive
Cumberland, RI 02864-8707