From your favorite gemstone to gemstones you've never heard of, we have fun facts and exclusive information in our new and improved gemstone encyclopedia.
“Anyolite” comes from the from the Masai word anyoli, meaning "green." It is also known as ruby in zoisite. It is a translucent to opaque rock composed of ruby crystals, green zoisite and black or very dark green pargasite. It is used for cabochons and decorative objects. It was first discovered in 1954 at the Mundarara Mine, near Longido, Tanzania. It has also been found in the Muriatata Hills, Kilimanjaro Region, Tanzania.
Apatite is the name for a mineral group as well as the generic term for many phosphates, but gem-quality apatite is a special gemstone found in a beautiful variety of colors. Apatite's various colors are often due to the presence of rare earth elements or natural irradiation. Because of its wide color range, apatite has often been mistaken for many other gemstones, including topaz, tourmaline, and various beryl varieties. Particularly rare in sizes over one carat, apatite is a relatively soft gem and when used in jewelry manufacture, is often set into more protective mountings that capture light yet safely display its beauty. The long-established sources for gem-quality apatite are Brazil and Mexico, but more recent African discoveries have thrust it into the spotlight once again.
Apophyllite is divided into three distinct species, fluorapophyllite, hydroxyapophyllite and natroapophyllite, depending on their chemical composition. It was once considered to be a single mineral, so if chemical composition is not yet determined specimens will still be referred to as apophyllite. It is commonly found as glassy prismatic, blocky, or tabular white to grayish or light pastel crystals. The name apophyllite comes from the Greek word meaning "leafs off," referring to its tendency to flake when heated.
The birthstone for March, aquamarine is one of the most popular members of the beryl family, a sibling to emerald, morganite, bixbite, heliodor, and goshenite. The color ranges, depending on the relative concentrations and location of iron within the beryl crystal structure. Aquamarine's tranquil color and crystalline clarity capture the beauty of the sea, which is fitting as its name is formed from the Latin words "aqua," meaning water, and "mare," meaning sea. A favorite among gemstone lapidaries, rough aquamarine is relatively easy to fashion, so lapidaries often create imaginative aquamarine cuts and shapes.
Aragonite's name is derived from the location of Molina de Aragon, Spain, the province where it was first discovered. Aragonite occurs in Agrigento, Sicily, Italy, in the famous sulfur mines, as well as on Mount Vesuvius, Italy. Aragonite specimens are highly prized by mineral collectors for their wide variety of forms, which include twins and pseudomorphs (uncharacteristic crystal forms). As an added bonus, many specimens are fluorescent as well as phosphorescent, a rare occurrence among minerals.
Arsenopyrite is the most common arsenic mineral, once known as arsenical pyrites. Its color is silver-white to steel-gray on freshly broken surfaces. It yields a garlic odor when heated and the fumes can be toxic. It may tarnish to form an iridescent layer. Although it has a reputation for being poisonous to humans, complex arsenic compounds are used in the treatment of disease caused by microorganisms.
Astrophyllite is golden-yellow to dark brown and usually forms as bladed crystals radiating from a common center. It gets its name from the Greek astron, meaning "star," and phyllon, meaning "leaf." It may also be translated as "star sheets" because of the interwoven star shapes that crystals sometimes form, and because of its strange luster, which can be metallic or pearly. Although there are occurrences of astrophyllite around the world, some of the finest crystals come from remote mountainous regions in arctic northern Russia.
Aventurine is a form of quartz, distinguished by its translucent to opaque appearance and the presence of mineral inclusions that give a shimmering or glittery effect termed aventurescence. The phenomenon of aventurescence is caused by small leaf-like or plate-like inclusions, usually mica, distributed throughout the host material. Light striking the surface of these inclusions is reflected back to the viewer, creating an eye-catching sparkle. While customarily green in color, aventurine may also be found in colors ranging from blue, orange, white, yellow, reddish-brown to gray.
Axinite is an uncommon mineral that usually occurs in long, flat, axe-shaped crystals, a trait that makes it highly desirable to collectors who enjoy adding various crystal forms to their collections. Its strong trichroism only adds to its special appeal. As it is rotated, different colors are displayed, including rich cinnamon browns, violets, blues or greens.
Azurite is a copper carbonate mineral found in the oxidation zones of copper deposits and is considered a secondary ore of copper. Color ranges from light to dark blue, with medium to dark blue being more common. The intensity of its hues is what makes azurite a popular collector's stone. Azurite is commonly found in conjunction with malachite, a green copper carbonate mineral into which it slowly morphs. A mix of the two minerals is known as azurmalachite. Azurite is soft (3.5 on the Mohs scale) and opaque. When used in jewelry, it is usually seen in the form of cabochons or beads.
This trade name refers to a natural mixture of azurite and malachite that is often banded and can be used as both a gemstone or in decorative items. The bold greens and blues beautifully intertwine to form unique mineral specimens or gems, each piece always one-of-a-kind.
This mineral is most often white or colorless but can form in an array of colors. It is prized among collectors for its various crystal forms and habits. Barite can be easily identified by its weightiness, as it is much heavier than most similar minerals.
A rare gem, bastnaesite is named after the Swedish locality where it was originally discovered in 1841, the Bastnas mines. Color can range from honey yellow to reddish brown and crystals vary from transparent to translucent in appearance. Valued by industry as a source of rare-earth elements, bastnaesite is rare, but has been found in small quantities throughout the world. It is difficult to cut because it is a relatively soft mineral, however, its high refractive index, combined with its rarity, make it an exciting gem to own.
Bayong is a hardwood tree from the Philippines. The wood is used to make beads and jewelry. The leaves can be woven into purses and baskets.
Benitoite is a single-source gemstone, meaning that so far, it has been found in only one place on Earth: San Benito County, California. Benitoite grows in relatively small crystals, only a portion of which are gem quality--further increasing the rarity and value of this unique gemstone. Gem-quality benitoite over one carat is incredibly difficult to come by. California's state gemstone, benitoite is especially prized by collectors for its strong dispersion, which rivals that of diamond in lighter material.
The name beryl is derived from the ancient Greek term for the same gem, beryllos; also the etymology for the element beryllium that is part of its chemistry. Some scholars believe the word beryl is related to the ancient trading city of Belur or perhaps has ancient Indian origins (being derived from the old Hindi word velurya or the Sanskrit word vaidurya). Varieties include emerald, bixbite (red beryl), morganite, aquamarine, heliodor (golden beryl) and goshenite.
Named for its beryllium content, beryllonite is a colorless to white or pale yellowish crystal. It is usually transparent with a vitreous to pearly luster, and is often heavily included. This rare gem is found in only a few places around the world, notably in Maine, USA.
Bismuth is rarely found naturally in its elemental form (even less commonly than platinum), but lab-grown crystals are gaining in popularity for their unique geometric formations (hopper crystals) and phenomenal iridescence. Bismuth is a silver-white metal, but an oxide layer forms immediately when crystals make contact with air. This produces an array of colors similar to that of a soap bubble or oil on water. The different colors are dependent upon the thickness of the oxide layer, which determines how light is reflected off of the surface creating a striking rainbow effect.
Red beryl or bixbite is the slightly purplish red to orange-red variety of beryl. It was discovered in 1904 in the Thomas Range of Utah by Maynard Bixby. Gem quality red beryl was found in 1958 in the Wah Wah Mountains of Beaver Creek, Utah. The material is typically included and faceted stones above 1ct are rare. Synthetic red beryl was produced in a Russian lab starting in the 1990’s but it is not known to be currently in production.
Black opal is the rarest and most valuable variety of opal. Black opal displays “play of color” and has a black, gray, dark green, dark blue, or blackish brown body color. Most black opal comes from Lightning Ridge and Mintabie, Australia, but it can also be found in Java, Virgin Valley, Nevada, and Wello, Ethiopia.
Blister pearls are large pearls that have intergrown with mollusks or freshwater mussels and are integrated with the shell. Solid “blister” pearls are akin to mabé pearls, but they are natural and not assembled. They are known to have a high luster and are more durable than mabé pearls. They are typically rounded or irregular in shape and have been known reach 2 cm in size. They are more often found in in larger Pinctadas molluscs. They are called “puku” in the Cook Islands. They are also found in freshwater river mussels in North America. The freshwater blisters pearls are often found in mussels with distorted shells and are come in irregular, round or button shapes. Snail blisters are created when small snails or mollusks invade the mussel shell. Blisters pearls have also been found in “Lion’s Paw Pearls” in Laguna Ojo de Liebre in Baja California, Mexico, and Conch pearls in the Caribbean.
Bloodstone is green jasper dotted with bright red spots of iron oxide. The green color is caused by small particles of chlorite, a silicate mineral or hornblende needles interspersed throughout the host material. Its distinctive reddish spots are caused by the presence of iron oxides.
Since prehistoric times, people have used animal bones for ornamentation. Their relative softness lends to beautiful carvings for both detailed figurines and jewelry, often as beads. Cultures without access to ivory often used bone for similar purposes.
Known for its lively, flaming color displays, boulder opal is in high demand by collectors and jewelry designers. As opposed to cut opal gems, boulder opal features small opal veins running through its matrix. The precious opal's rainbow of colors make a dramatic contrast to the rich earthy reds and browns of the host rock, creating a one-of-a-kind display.