Those little glass
half-marbles you find so frequently in
craft stores and
pet shops. Most people use put them in vases with cut
flowers, or put them in
aquariums for decoration. They are also frequently sold as the gamepieces for the game
mancala.
dragon's tears come in many colors and have a quasi-metallic/perlescent shimmer to them. They can be (*if* they are psychically clean) very powerful tools in spellcasting/ritual. They can act in some ways like gemstones of their color, but can be charged with almost any needed energy. They can be used to cast circles and are also often are used/given as "offering" or token to the elements or the earth in which one is working. Dragon's tears can also be used very well to make a set of runes for runecasting.