Gemstone List

Abalone (Mother of Pearl)^SP,OR: From the paua or abalone mollusk shell. Paua has the blue-green iridescence on the inside of the shell. Are often sandwiched with a plastic resin in the middle to give some thickness to the bead or cabochon. Hardness 3.5.

Amazonite^SP: A blue-green, milky color, it is a soft stone; has a silky sheen; named after Amazon women warriors. Feldspar Group. Hardness 6.0.

Apatite^SP: Blue-teal, cloudy or clear, brittle, scratches easily; is a soft stone. From the Greek to deceive, as it closely resembles stones from the beryl family (aquamarine). Vitreous or Glassy luster. Transparent or opaque. It is the same as the mineral that makes up teeth. Sometimes is heated to increase the blue color (usually grades A or B). Grades: B-clear, C-dark opaque blue, C-dark opaque blue with some brown. Hardness 5.0.

Aquamarine^SP: From the Latin "Water of the Sea." Pale blue, clear or cloudy, a hard stone. Dichroic-color intensity changes depending on angle of view'. Assume it is heated (to 400°C), a common and usual treatment to decrease the greenish cast so the blue color is more obvious. The cloudy, opaque stones are considered flawed, but they are also beautiful in their own right. Birthstone for March, Anniversary stone for the 16th and 19th year. Beryl Group. Hardness 7.5.

Aventurine, Blue: A blue quartz, a hard stone. Hardness 6.5.

Celestine: "Of the Sky." Pale blue, has shiller, or Aventurescence. A soft stone. Hardness 3.5.

Chalcedony: Very pale lavender-blue, an Agate from the Quartz group; translucent; banded blue is called Blue Lace Agate; a hard stone, often with Drusy. Hardness 7.0.

Chrysocolla^SP: Blue and green, has a greasy luster. Hardness 7.0.

Coral^OR: Coral is the skeletal remains of coral polyp animals which live in the ocean at depths of 1' to 1,020'. There are 2 main types: Stony and Proteinaceous. Proteinaceous Coral is made of hair-like protein, and is naturally black or gold; sometimes it's bleached. Stony Coral is more common and is naturally an off-white/tan, pink, or red; is often dyed. Stony Coral also comes in other types: Bamboo and Sponge (these types are not endangered). Bamboo Coral is formed in tree-like branch shapes. Sponge Coral is not as compact as other corals,; because the polyp homes rarely grow shut, it results in patterns similar to a sponge. Because of these holes, sponge coral is usually stabilized. Sponge Coral is either a red-orange or blue-gray color. The blue is often enhanced with a blue dye. The endangered types of coral are Staghorn and Elkhorn Corals. Hardness 3.5.

Druzy: Fragile, natural state of tiny crystals found inside geodes. Since Druzy is Quartz, it is inherently hard and durable, but the structure of the druzy makes it fragile, as the crystals can break off if not handled with care. Hardness 6.5.

Dumortierite: Dark blue, sometimes with dark gray areas, a hard stone. Quartz group. The polished surface will usually have pits. Distinguished from Lapis Lazuli by a lack of gold-colored flecks. Hardness 7.5.

Hemimorphite: Pale white-blue, is stabilized, a normal treatment, brittle. Hardness 5.0.

Iolite^SP: "Water Sapphire," though not a sapphire. Pleochroic-has different colors (almost clear to violet-blue) when viewed from different angles; blue-violet, grey, and near colorless. Greek for violet. Thin pieces were used like a polarizing filter by the Vikings to help them navigate in the open seas; the sun could be seen through haze or clouds. Iolite is usually not treated. Hardness 7.0.

Kyanite^SP: Medium blue, brittle, fibrous; ethereal & shimmery-simple Chatoyancy. Trichroic. Greek for blue. Hardness 4.0-4.5 when cut parallel with the crystals, and 6.5 when cut across the crystals.

Labradorite^SP: Gray with blue, green, and yellow reflections, with a strong, directional Iridescence or Labradorescence at different angles. The stone is named for the area it is found-Labrador, Canada. It is Translucent to Opaque, with light to dark grey body color with needle-like inclusions of black magnetite, often shows some fractures. Hardness 6.0.

Lapis Lazuli^SP: Lapis is one of the oldest gems; it's been found in jewelry from 5,000 B.C. The name is Arabic for Blue Stone. A soft stone with tiny flecks of pyrite (gold); is the 'sapphire' referred to in the Bible. It is often coated with wax to improve its appearance. Birthstone for December, the stone for the 7th and 9th Anniversaries. Hardness 5.0.

Larimar^SP: A robin's egg blue mottled with white, found only in one location-inside the crater of an extinct volcano-in the Barahona Province, Dominican Republic. It was always known to the natives, but wasn't known to the rest of the world until 1974. It has a silky luster. Hardness varies from 5.0 to 7.0 (darker blue stones).

Moonstone^SP: White, often with blue reflections. Blue or Rainbow Moonstone are the most valuable. Shiller or Adularescence: light reflects off inner alternating layers of its minerals. Not treated. Was popular with the Romans who thought it was formed out of moonlight. Used in Jewelry since 100 A.D. Birthstone for June, stone for 13th Anniversary. Feldspar Group. Hardness 6.0.

Mother of Pearl^OR: Pale beige or bleached to white, from the inner layer of a mollusk's shell; a soft material. Shows an Orient type of Iridescence. Hardness 3.5.

Pearl^OR: Easily scratched, dries out with age; cultured: is grown by man in a mollusk in fresh water. Stone for several Anniversaries, see chart. Hardness 3.5.

Petoskey: Beige, a fossilized coral of the Hexagonaria from 350 million years ago; patterns are cross sections of coral branches; named after an Ottawa Indian Chief. The petrification or fossilization process hardens the original coral with a hardness of 3.5 to 7.0. Hardness 7.0.

Prehnite: Pale translucent green with black tourmaline needle inclusions are common. Named for a Dutchman, Colonel H. Von Prehn in the 1700's. Hardness 6.0.

Quartz, Clear^SP: Rock crystal is a pure form of quartz. Transparent, with a Vitreous or Glassy luster. Quartz is the single most abundant mineral on Earth. Hardness 7.0.

Snow Quartz: Off-white form of quartz due to micro-inclusions, also called milky quartz. Opaque. Hardness 7.0.

Sodalite^SP: Dark blue with white (which distinguishes it from Lapis), named for its sodium content; a soft stone. Hardness 6.0.

Tanzanite^SP: Heat treatment is normal which increases the blue color. Discovered in Tanzania in 1967 when a rock rolled into a campfire and turned violet. Found only on a 5 square mile hilltop at Merelan. Pleochroism-different colors at different angles: deep violet, pale violet, and a murky brown grey. A Birthstone for December. Hardness 6.5.