How Do You Identify Rocks, Minerals and Gems?

Identify minerals and gems at and; by definition, rocks lack a particular chemical composition or structure and cannot be identified per se. The minerals that compose a rock may be identified using online tools at these websites.

On the main page at, hover the mouse over the Minerals tab, and then click Filter by Color beneath the Filter Minerals section on the drop-down menu. Click a color to display a list of minerals of that color, and then refine the search with options near the top of the page, such as Chemical Group, Crystal Group, Streak and Hardness. Click the Submit button to display a list of minerals with the chosen properties.

Click a mineral on the list to display photos and other details, such as the mineral's specific gravity, luster and environment. To differentiate it from minerals with similar properties, click the name of a mineral beneath the Distinguishing Similar Minerals section midway down the page, and then compare your sample to each to find the best match.

By definition, gemstones have particular cuts and polishes and are best identified by comparing samples to photos of other identified gemstones. To identify a gemstone at, hover the mouse over the Gemstones tab on the main page, select a color, and then compare your sample to photos of gemstones displayed on the page.

To identify a mineral at, click the Gem and Mineral Identification tab on the left side of the main page, and then click the link associated with the color of your sample to display photos and other details of gems and minerals of that color.