A gemstone or gem (also called a precious or semi-precious stone, a fine gem, or jewel) is a piece of mineral which, in cut and polished form, is used to make jewelry or other adornments. However certain rocks, (such as lapis lazuli) and organic materials (such as amber or jet) are not minerals, but are still used for jewelry, and are therefore often considered to be gemstones as well. Most gemstones are hard, but some soft minerals are used in jewelry because of their luster or other physical properties that have aesthetic value. Rarity is another characteristic that lends value to a gemstone. Physical characteristics that make a colored stone valuable are color, clarity to a lesser extent (emeralds will always have a number of inclusions), cut, unusual optical phenomena within the stone such as color zoning, and asteria (star effects). Color zoning is the uneven distribution of coloring within a gem.
The gemstones we’ve highlighted here are some of the most common and available. Some gemstones are so rare that they are only known to gemologists and within the trade. Click on any of the gemstones below for more information.
 Alexandrite |
 Amethyst |
 Aquamarine |
 Citrine |
 Emerald |
 Garnet |
 Iolite |
 Jade |
 Kunzite |
 Lapis |
 Moonstone |
 Morganite |
 Onyx |
 Opal |
 Peridot |
 Quartz |
 Ruby |
 Sapphire |
 Tanzanite |
 Topaz |
 Tourmaline |
 Turquoise |
 Zircon |