Don’t let this 22K ring intimidate you! You will find that working in
this metal will be an absolute joy to work in, and because of its
high gold content, it will form easily and be pretty hard to
accidentally melt, as you are soldering it together.
You’ll want a high karat (hard) solder to make an invisible seam, of
course, and that will take some real heat to melt into the seam well.
Make sure that seam is as tight as humanly possible.
Your plan to put a hammered finish on the ring is a good one, and
that will harden up the ring really well.
You will have to slightly “over-engineer” this ring, because of its
inherent softness, but your hammered finish will really help make
the ring stronger. The question about casting versus fabricating
really depends on the shape you want to achieve, but if it’s a fairly
simple band, and you plan to hammer it, I’d go for fabricating it,
absolutely. Fast and strong. I’d suggest making the ring a full size
smaller, then when you planish (or hammer) the outside of the ring,
it will get larger by about a size, depending on how hard you hammer
the metal. If you have a ring stretcher, you can use that to gain
any extra size you might need for the finished size. If you happen to
blow out the seam, just resolder, although the soldering will again
resoften the ring somewhat. If you alloy your own gold, starting
with 24K, you can alloy gold to absolutely any karat or color you
might desire, which is very liberating. However, marketing that ring
commercially would suggest that you stay with “standard” qualities
of gold content, 24K, 22k, 18K, and 14K, as examples.
The hallmark stamps are easy to find for these karats.
Others will have their own take on this (Count on it!)
(Does someone out there have a good way to remember the difference
between Karat and Carat? I’m not always sure I remember how to tell