Making your own silicone molds is useful because you can customize them for different cake designs.
On Wednesday I wrote about where to get the materials for mold-making. Here's the entry for reference if you missed that.
Amazing Mold Putty and a Peace Dollar, since they look nice and they're deep enough to make a good impression. Coins that are really thin won't necessarily be good to use because they'll be hard to get out of the mold without distorting them.
until you get a consistent color. Make sure that you check the work time on the putty, since different formulas have different times that they take to harden up!
As long as you've let it cure according to the instructions, it should be ready to use right away. The impression on this one wasn't as distinct as I'd like it to be, but it was an old Silver Dollar, so that happens! It looked fine with some luster dust on it, and if I was going to be making a treasure chest or something along those lines it would work fine.
Next- Multiple cavity molds