How to Identify Crystals & Minerals

Find several raw crystals. Raw is best because tumbled crystals no longer show the shape in which they grew in the earth. Raw crystals are not tumbled and show the natural growth patterns of the crystals. Good specimens are available at your local New Age Shop.

Pick up each crystal and look at its shape. If you have a crystal cluster, choose the largest crystal to examine. Each crystal should have several faces. If all of the faces are the same width, the crystal is isometric. If two of the faces are at right angles with a longer third face, it is tetragonal. Hexagonal crystals have six faces and are shaped like pyramids. Check Mineral Matters from the San Diego Natural History Museum in References for a complete list of shapes.

Look at the colors. See if the crystals have a metallic sheen like bronze, gold, silver or shiny peacock colors. Metallic crystals are usually ore, like copper, pyrite or nickel. Non-metallic colors indicate semi-precious stones like clear quartz, purple amethyst or dark red ruby.

Heft each crystal in your hand and line them up from lightest to heaviest so you can keep track. Very heavy crystals are usually ores like hematite and pyrite while medium-heft crystals are stones like garnet and fluorite. Light stones indicate porous or brittle stones like selenite and gypsum.

Write down the qualities of each crystal and look them up in your identification guide. Look for a good guide with color photographs and the minerals listed in alphabetical order. Smithsonian Handbooks publishes a handbook with large photographs and a long list of minerals.