Most rockhounds specialize, rather than try to collect all the 1,500 known minerals. Colorful and beautifully shaped crystals are prized by all collectors. Petrified woods and fossils are interesting specialties. Collections of semiprecious stones such as agates, zircons, garnets, and amethysts may lead to gem cutting and jewelry making. This offshoot of mineral collecting has become a major hobby in itself.
Some collectors make dramatic exhibits with fluorescent minerals.
In normal light the specimens appear dull and unattractive. In a dark room, exhibited under purple light, they glow in spectacular colors. Inexpensive argon electric bulbs may be used to illuminate a box of specimens. Many rockhounds band together in a mineral or gem society. Local and state societies belong to one of six regional federations.