I'm working on a type of banish/protection charm and was looking for any insight about charging a crystal with a small open fire. I would like it to be a heated charge at night. I was looking in to candles but as a new practitioner, and each color of candles having multiple purposes I wouldn't want to divert its purpose. Is it possible? Is there any precautions I should take? Please, if you have any experience with this I would love to read it.