Rings have been worn through the ages, and often have significant meaning. The ring is put on the cone and its size is read where it fits snugly on the cone. To size a finger, a finger-ring gauge is used. The rings are marked with their size and the person determines which one fits well. Another, less accurate method, is a cardboard card with cut-out holes marked with the ring sizes.
Rock crystal is the purest form of quartz and a semi-precious stone .