For this video I used a stick that I found on the ground which had been blown down in a storm. If you are using new materials in a polymer clay project it’s a good idea to test how they will react in the oven. I was not worried about the stick igniting at 120 degrees C, but with certain woods you may get sap bubbling out. It’s best to do a test bake before you have spent time working on you polymer embellishments.
I wonder if cold porcelain would work. I'd like to have your advice. Here in Argentina, the price of polymer clay is about 7 times the price of cold porcelain.
I've never used cold porcelain so unfortunately I can't really advise. I think joining different materials such as sticks and crystals may have problems with cracking if the cold porcelain shrinks as it dries. Perhaps you could try with a smaller piece to see if it works?