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Diamonds in the rough, note the regular octahedral forms and trigons (of positive and negative relief) formed by natural chemical etching. Photo credit: Wikimedia.

Gemstones


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A gemstone is any rock or mineral that may be used for ornamentation or jewelry. Gemstones usually are minerals prized for their color, beauty, rarity, and endurance. Typically, they are cut and polished to bring out their natural beauty. Even diamonds must be cut into their familiar faceted shapes to really sparkle. Colorado has more than thirty varieties of gemstones including diamonds, rhodochrosite, and aquamarine. The largest faceted diamond sourced in the United States (16.87 carats) was found in Colorado. The official state gemstone is aquamarine, a beautiful blue mineral mostly found around the 13,000-foot level on Mount Antero. Other notable gem-quality minerals that have been found in Colorado include amazonite, garnet, topaz, tourmaline, lapis lazuli, quartz crystal, smokey and rose quartz, amethyst, turquoise, peridot, sapphire, and zircon. Agate, chalcedony, and jasper, three varieties of cryptocrystalline quartz, are also found in many places.

Diamonds in the rough, note the regular octahedral forms and trigons (of positive and negative relief) formed by natural chemical etching. Photo credit: Wikimedia.
Diamonds in the rough, note the regular octahedral forms and trigons (of positive and negative relief) formed by natural chemical etching. Photo credit: Wikimedia.