What Do Raw Rubies Look Like?

Color

• The ruby is a variety of the mineral corundum, which is the crystal form of aluminum dioxide. Corundum produces several colored gemstones that include a range of colors from red, pink, orange, purple to a brownish-red. The medium- to dark-colored red stone is called a ruby. All other colors are referred to as sapphires. The color of the gemstone created out of the corundum is directly affected by the iron and chromium content of the stone. Chromium produces the red color--the higher the level of chromium, the darker red the stone.

The Stone

• Raw or rough rubies can be found embedded in an area of corundum, such as a cliff or large rock formation or in a piece of corundum that looks like a rock. It will be a medium- to dark-red color. The color of the corundum varies depending on the mineral content of the soil within the area. It may have a heavy weight for its size. It will need to be cleaned, cut and polished to gain the appearance of the gemstone.

On-site Testing

• When a possible ruby is found, it is important to verify that it is a true ruby. The surface of the raw ruby will be rough and sandy. If water is poured on it and the stone stays rough and sandy, it is not a ruby. The hardness of the stone will be scratched with several different objects. The only thing that should be able to scratch a ruby is a diamond. The shape of the ruby should be that of a crystal; it will have one or more naturally faceted sides.

Off-site Testing

• A ruby will leave a streak when pulled across a ceramic tile. A chart of gemstone streaks can be compared to see if the stone is truly a ruby. Chemical and physical tests can be performed on the ruby. They include tests for specific gravity, refractive index, light dispersion and color changes. A gemologist is the best individual to conduct these tests.

Raw rubies in North Carolina

• The North Carolina region of the United States provides several locations for rock hunters to find rubies and sapphires. Small tutorial classes are provided teach the rock hunter how to identify the corundum that holds the gemstone crystals. Small entrance fees are charged with a limit as to how much raw material is removed from the sites.