Hey, i had a question about one of your How-Tos. How did you get the gems off the molds for your raven once they were done hardening?
I use a mold release on the molds before I add the resin, so once the gems are hardened, I just give the molds a whack* with a hammer and they pop out.
*Or several lighter taps, which is generally better and less harmful to the mold/gems.
elfgrove also tested using other methods of mold release...things, and you can see her results here. (Aka dishsoap seems to work as well as mold release.)
If you've already got your gems cast and you haven't coated the molds with something before doing so...uh...I'm not entirely sure what you'd do, other than trying to get them out the way you'd normally do it. I'd be more concerned with saving the mold than the resin myself at that point.