Some semi-precious stones are amethyst, opal, tanzanite, pearl and onyx. Garnet, moonstone, turquoise and peridot are also considered semi-precious. The expansive list also includes tiger's eye, topaz, coral, malachite and many others, says Jewelry Information Place.Continue Reading
Beryl is also a semi-precious stone and comes in different forms including aquamarine, heliodor, morganite and red beryl. Emeralds are a form of beryl, as well.
A semi-precious stone is a portion of a mineral that is cut and refined, and the stones are often used for jewelry or decorative details. The difference between precious and semi-precious stones is strictly commercial. Precious and semi-precious stones are all classified as gemstones, but precious stones are just marketed differently. Some stones that are considered precious are diamonds, sapphires, rubies and emeralds.
Higher prices for precious stones can be obtained because of each stone's brilliant color, clarity and rarity. Historically, pearl and opal were considered precious stones, and at one point amethyst was, as well, until a large amount of amethyst deposits were located in Brazil, making the stone less rare and downgrading the stone to a semi-precious status. The U.S. Federal Trade Commission has considered banning the terms "precious" and "semi-precious" to make the gemstone market more customer-friendly, says Gem Select.Learn more about Precious Metals & Gems