what is the scrap?
new wire/ sheet clippings?
old casting scrap?
what colour gold?
i’m no expert, but it sounds like you are work hardening the metal
and not annealing properly, maybe over heating the metal and making
it brittle? maybe under heating? annealing too much, quenching
instead of air cooling? here’s one article i retrieved from the net:
i’m setting aside some 18k for a similar ring, i’m going to use it
in a cuttlefish casting.
hth,
richard