Is it possible to bake in a copper jello mold?

it depends on what it is lined with, I found this article

Copper Cookware is Excellent for Certain Uses; One other surface favored by chefs for sauces and sautés is copper, which excels at quick warm-ups and even heat distribution. Since copper can leak into food in large amounts when heated, the cooking surfaces are usually lined with tin or stainless steel. If not linds, it can be dangerous to eat food cooked in unlined copper.

I also did a little research on this. I found that it all comes down to what the mold is actually made of. Many of these molds are different levels of copper and other elements. The comments given are very different. Some baked in copper with no trouble. Others baked in it and failed. Their food turned green/blue and had bad taste. Sorry, I wish I had better news.

I would be concerned about what kind of solder was used and what type of coating it has on it, and if it is really copper or just copper color.

Thank you everyone for your answers. Have a happy Thanksgiving.

in culinary school, we were taught that certain acid based foods, (tomatoes, citrus, etc.) turn toxic when cooked in copper. That’s how cast Iron came to be. (followed by tin.) so the best rule of thumb is to NOT cook edibles in copper. Strictly sculptural purposes.