Used by many for smudging and burning, herbs, wood, resin, cones etc. When used clean, it can hold crystals and other sacred items for your alter. Never put a charcoal directly on a shell or bowl. They get very hot an can burn yourself or the table it's on. Always use about 2" of sand in your shell or bowl as a heat buffer. These beautiful shells are made by Mother Nature so the are around 3"-4" long and very in size and shape. They are all beautiful and the one you choose is exactly the one for you. These shells are naturally imperfect, so there may be chips around the edges. They where well used by their previous tenant, so please be aware of this before you order. Thank you. :)