Gemstones Dictionary

Alexandrite: June's birthstone. A variety of chrysoberyl. It exhibits an emerald green color under daylight and red to violet under artificial light.

Amethyst: February's birthstone. A violet transparent variety of quartz.

Aquamarine: March's synthetic birthstone. The light green-blue variety of the mineral, beryl.

Bloodstone: March's natural birthstone. Dark green jasper with red spots and patches.

Diamond: April's birthstone. The hardest of all known substances, the diamond is also the most valuable precious gemstone. They are usually nearly colorless although they sometimes are found to be yellow, brown, violet, green, blue, black, and red.

Emerald: May's birthstone. Emerald is the green variety of the mineral, beryl. Aquamarine is the blue variety of beryl.

Garnet: January's birthstone. A family of closely related minerals that are known for their brilliance. They come in a variety of colors.

Imitation: A gem with a different chemical composition than the the gem it is meant to imitate.

Jade: A gemological group including two chemically different minerals, jadeite and nephrite. The two minerals have similar properties. They are both very tough and used in jewelry and carved objects.

Opal: October's natural birthstone. A noncrystyalline gem that is formed when liquified silica seeps into fissures and hardens. Transparent to opaque opals are found in a variety of colors. They are prized for their vibrant flashes of color. Opals are often brittle due to their porous nature.

Pearl: June's natural birthstone. Pearl's are unique in that they are found in the water rather than the ground. They are formed when a shellfish covers a parasite with layers of nacre which is the substance which makes up a shell.

Peridot: August's synthetic birthstone. A transparent to translucent mineral species that occurs in a variety of green tones.

Precious Gemstone: The most valuable gemstones: diamonds, sapphires, rubies, and emeralds.

Ruby: July's birthstone. Uncommonly known as corundum, it is the 2nd hardest known substance, although diamonds are 4x harder. Rubies and sapphires are the same mineral. Red corundum stones are rubies. All other are sapphires.

Sapphire: September's birthstone. Uncommonly known as corundum, it is the 2nd hardest known substance, although diamonds are 4x harder. Corundum in all colors except red are known as Sapphires. Red corundum is known as a ruby.

Sardonyx: August's natural birthstone. Agates with straight parallel bands or layers alternating between layers of reddish-brown with other colors.

Semi-Precious Gemstone: Numerous gemstones that are not in the category of precious gemstones.

Synthetic: A gem with the exact same chemical composition as it's natural counterpart.

Tanzanite: A transparent blue gem discovered in Tanzania in 1967.