I have not, but I have a large (about half life size) skull mold that is intended for chocolate and it is not nearly as heavy or sturdy as an ice tray. I would give it a go.
I did a search for mini skull chocolate molds and I found a couple -- maybe you already saw them -- the links are enormously long but I will post them --
I got to take a class with a world famous chocolatier, his name is on the tip of my tongue...he had a culinary school that closed suddenly, his wife was famous in chocolates too...but his assistant in that class became a famous caker, on tv cake competitions & did a bunch of those online classes -- james somebody or other --
and he, the chocolatier, said they never wash the molds, they scrape off the excess all around but never wash in hot water-- I mean I wash mine and of course I'm not world famous either but anyway he used the hard inflexible p!astic molds -- he said they are designed to bring out the beautiful shine in the chocolates -- there's a coating in there you don't want to wash away --
just random chocolate musings --ewald notter is his name!
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