This is a variation of my Dinosaur Fossils post, but uses a snowflake ornament instead.
1. I cut a 6 inch square piece of cardboard to hold my cast until it dried. I took a handful of clay (left over from ceramic projects), rolled it smooth, and pressed it into almost a 6" diameter pancake and centered in on my cardboard.
2. I pressed the wooden snowflake firmly into the clay to make an impression, and removed it carefully. Some very thin ones break pretty easily, so you must be careful.
3. I cut a strip of heavy watercolor paper (posterboard would work too) about 14" long by 2" wide. Overlapping the edges a bit, I stapled the ends together to make a ring.
4. The paper ring is centered over the snowflake impression, and pressed firmly into the clay until it hits the cardboard base. Plaster is mixed up to a pudding consistency (best for adults) and pored into the clay mold. Wait about an hour until the plaster is pretty well set before you tear the paper away and peel off the clay. Paint with gold or silver paint. Seal with a spray varnish.