Hi:
I look in from time to time to see what people are talking about. Glad I caught
this one. OK, on MOST of this story nothing I can say is useful , but as a
metalsmith I can say what the difference is between the sets of shoes.
Annealing with a torch and quenching is going to take most of the stress out of
brass, but not all. The brass will turn brown to black from the air burning some
of the copper.
Furnace annealling will make the brass as soft as possible, and the air in the
furnace is usually "dead" air. Air with most of the O2 used up. Brass can come
out a soft golden color from minor tarnish of the zinc in the alloy migrating to
the surface.
Gold can and will "evaporate" if melted without flux and held at that high heat
for long enough. Anybody refining gold should know this and will work to
prevent it. Gold can be vapor deposited , but not under the normal refiners
conditions.
Last bit , pure gold melts about 400 degrees F higher than brass, so for any
gold vapor to be floating about in the furnace the brass would be a puddle.
Happy to help.
Daniel Tokat