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.
Although this phosphate mineral has a hardness of 5.5, brazilianite is fragile due to its perfect cleavage and brittle nature. Most brazilianite is chartreuse to pale yellow and forms in granitic pegmatites associated with tourmaline and apatite.
Bronzite is an iron-bearing variety of enstatite distinguished by its green-brown color and bronze-like sub-metallic luster with fibrous inclusions. Enstatite is a silicate and a member of the pyroxene group. Appreciated for its sheen, bronzite is sometimes polished to make small ornamental objects.
Named in honor of its discoverer, Anastasio Bustamante, bustamite is a member of the wollastonite group. Similar to rhodonite in appearance, it is usually found as a massive transparent pink material that may be cut into cabochons or carved into figurines.
Bytownite is a rare variety of feldspar named for deposits found in Bytown, Canada (now Ottawa). Some forms of this gem distinctly resemble the gemstone andalusite, another member of the feldspar group.
Named for its calcium content, calcite is one of Earth's more abundant minerals-- you've probably seen it many times and not known exactly what it was. It is found in marble and limestone, as well as other rocks used in industrial settings. Gem-quality calcite, however, takes on a quite different look. You may have seen colorless calcite crystals used as examples for double refraction, but it also forms as white, gray, yellow, pink and green gems. Material is often faceted or polished en cabochon, or carved into ornamental objects.
Also called "rainbow calsilica," this is a man-made material that displays vibrant layers of bold color. It consists of a mixture of calcite, plastic and coloring pigments. This unique stone is often used in jewelry and carvings to show off its distinctive coloration.
Capiz Shells come from the province of Capiz and the island of Samal in the Philippines. The shells are often called windowpane oysters because they have been harvested for thousands of years for use as windowpanes. Capiz shells are also used today in chandeliers, lampshades, decorative objects, clothing decoration and jewelry. The shells are translucent in their natural state and turn opaque when heated. When shells are heated for longer periods of time, they turn a smoky brown color. Shells are also dyed fashionable colors.
Carnelian is a translucent orange to red variety of chalcedony. Uniformly colored cryptocrystalline quartz, its red tints are caused by traces of iron oxide. The name is derived from the Latin world for flesh, carne, due to its orangey red color. Carnelian has been appreciated since antiquity, and is one of the first known materials ever to be used as a gemstone.
The name Cassiterite is derived from the Greek word kassiteros, meaning “tin.” There are very few tin minerals, and cassiterite is the best known one. Gemstones fashioned from cassiterite are quite striking. This is due in part to its high dispersion, which is nearly double that of diamond. It is especially prized by gemologists and mineralogists for its unusual, twinned crystal formations. Durable and dense, it has been used as the chief ore of tin throughout the ages. Cassiterite often exists in placer stream deposits where it collects as rounded, water-worn pebbles.
Very distinctive in appearance, cavansite is a rare, not to mention strikingly beautiful, blue mineral. Its name is derived from its composition: calcium, vanadium and silicon. Only discovered in the 1960's in Oregon, cavansite is highly sought after by mineral collectors across the globe. Found in a scant few locales, cavansite sources include Brazil, India, New Zealand and Oregon USA. It is renowned for its stunning deep blue hues that are sometimes vivid enough to be described as "electric blue."
Celestite, also called celestine, is named for the Latin coelestis, meaning "heavenly," in reference to its often sky-blue color. This unique gem often forms beautiful transparent to blue tabular crystals, but it can also be colorless, white, light red, green, blue or brown.
Named for the Latin cerussa, meaning "white lead," cerussite is a lead carbonate mineral. Its crystals form in several different habits when carbonated water interacts with other lead minerals. Prized by mineral collectors for its twinned crystal formation, cerussite is usually transparent to translucent with no color to white, gray, brownish or greenish. Although too soft for jewelry, cerussite is occasionally faceted for collectors; however, it presents challenges to lapidaries due to its soft, brittle nature.