How to Identify Semi Precious Gems

If you've found some shiny stones in a natural location, trying to Identify semi-precious stones can be an entertaining undertaking. Of course, gemologists can run tests to accurately name the gem--a good idea if you plan on selling it--but for the average collector, a good eye is all you need in order to "guesstimate."

Instructions

1

Check the hardness of the stone. If it feels malleable or rough, you may have a mineral like the iron oxide hematite, instead of a rock.

2

Hold the stone up to the light to inspect its brilliance. Semi-precious stones generally contain crystals that are able to reflect light.

3

Look for any optical effects. Asterism, or a star effect, is common in rubies, sapphires, or garnets. Some effects are indicators that the stone is actually not a gem. For example, iridescence is most often found on opal, ammonite, and moonstone. A glitter effect, called aventurescence, is in sunstone and quartz.

4

Note the color. After you know you have a real semi-precious stone, color is the first indicator of what type of gem you have. Amethysts are generally purple and aquamarines are light blue. Citrine is usually yellow, topaz is orange, garnet is red, and peridot is a light green. However, don't make this your only identifier as colors can be misleading. Sapphires, for example, can also be green, pink, or even clear.

5

Check your guesstimate against a reference book or a website. With some practice, you will become more accurate in your identification of semi-precious gems.