Whether it’s understanding gemological or jewelry terms in an article you’re reading or simply gaining a greater understanding of the world of jewelry and gemstones, our Jewelry & Gem Dictionary is a handy reference guide. And, unlike most dictionaries, ours makes for interesting reading all on its own!
Baffa diamond is actually rock crystal and not a real diamond.
A baguette cut is a stone (usually a diamond) that has been cut into a long, rectangular shape. Baguette means “stick” or “rod” in French.
Bakelite (also called catalin) is a dense, synthetic resin that was used to make jewelry, game pieces, and many other things. Bakelite was patented by L.H. Baekeland in 1907. Bakelite plastic is made from carbolic acid and formaldehyde. Bakelite pieces are molded, extruded, or carved. When one Bakelite color is inlaid into another, interesting designs like polka dots can be made. Bakelite was first used to imitate amber. The bangle above is “butterscotch” bakelite
A bail is a triangular finding that attaches a pendant to a necklace.
A band is a ring that is made from a thin, flat, ribbon-like strip of material (usually metal).The band can be unadorned or decorated. Wedding rings are often bands.
Banded agate is a type of agate with distinct layers of color.
A bangle is a stiff bracelet. Some bangles have a hinge while others are solid and must be slipped over the hand.
BAR AND RING CLASP
A bar and ring clasp (also called a toggle clasp) is a jewelry fastener in which a bar can be inserted into a ring to fasten a pice of jewelry. It is used to attach the two ends of a necklace or bracelet.
BAR CHANNEL SETTING
Individual metal bars separate the gemstones. The metal is molded around a gem to lock it in place.
‘Baroda Gem’ is a trade name for a colorless glass stone with a foil back.
Baroque is a term that refers to irregularly-shaped stones or pearls.
Baroque pearls are irregularly-shaped pearls. Baroque pearls can be natural or artificial.
A bar pin (also called a bar brooch) is a long pin that is worn horizontally.
A barrel clasp is a jewelry fastener that resembles a barrel. The two pieces of this clasp screw together. It is used to attach two other rings or links of a necklace or bracelet.
A barrette is an ornament worn clipped into the hair.
Base metal refers to non-precious metals. Base metals include copper, zinc, tin, and lead.
Basse-taille (meaning “low cutting” in French) is an enameling technique in which the underlying metal (usually gold or silver) is carved in low relief (the metal’s surface is cut away by engraving or chasing, producing a sculpted surface). The highest point of the relief carving is below the surface of the surrounding metal. Translucent enamels are applied over the carved metal, allowing the design to remain visible through the enamel. The hue of the enamel changes with the depth of the glaze, resulting in subtle variations in color over the high and low design elements.
A baton is a stone that is cut in a long, thin rectangular shape. A baton is larger than a baguette.
A bayadre is a pearl necklace that has many strands of pearls twisted together.
Beads are small objects, each with a hole through it for stringing. Beads are made of glass, stones, wood, plastics, seeds, and ceramics.
A bell cap is a jewelry finding that is used to convert a hole-less bead or stone with into a pendant. A bell cap is glued onto the bead or stone and had a loop for attaching to the piece of jewelry.
Benitoite is a rare, blue gemstone that is found mostly in the San Benito River in San Benito County, near Coalinga, California (lesser quality benitoite is found in Mont St. Hilaire, Quebec, Canada). Benito means “blessed” in Spanish. This gemstones is strongy dichroic; although Benitoite is blue when viewed from most directions, it appears colorless when viewed in a single direction (the c-axis). Some unusual Benitoite is blue, but pink or orange when viewed through the c-axis. Benitoite is BaTiSi3O9 (Barium Titanium Silicate); no one is sure what element causes the blue color of benitoite, but it may be iron. Benitoite has a hardness of 6 – 6.5, a specific gravity of 3.68, and a refractive index of 1.757 – 1.804. Benitoite has a very unusual crystalline shape – it is the only known ditrigonal-dipyramidal crystal. Large stones (over 1 or 2 carats) are exceedingly rare. Benitoite was discovered in California in 1907, either by Mr. Hawkins and T. Edwin Sanders or James Marshall Couch (the story is in dispute). Heat-treated benitoite becomes orange; these stones are more expensive. Benitoite is California’s official state gemstone (since 1985).
Beryls are a family of gemstone that include emerald, aquamarine, beryl (green), red, morganite (yellow), and heliodor (pink). Beryl has a hardness of 7 – 8, a specific gravity of 2.6 – 2.9, and the chemical formula Be3Al2SiO6. Internal flaws in beryl gems can be hidden by treating the stone with oil (this is often not disclosed to the buyer).
The bezel is the part of a cut stone that protrudes above the edge of a setting. The bezel is also known as the crown.
A bezel setting is a way of setting a stone in which the stone is held by a band of metal around the outside of the stone.
A bib necklace (also known as a collarette) is a short necklace with flowing ornaments in the front.
Birefringence is another name for double refraction. and is the difference between the highest and the lowest refractive indices in doubly refractive gemstones. In doubly-refractive stones, the light entering the stone is split into two light rays, and the rays travel in different paths. These stones have more than one refractive index. Calcite, peridot, zircon, tourmaline, and titanite are doubly-refractive stones.
In the 1930’s, the British and U.S. jewelry industries assigned stones to the months of the year as follows: January – Garnet February – Amethyst March – Aquamarine April – Diamond May – Emerald June – Pearl or Moonstone July – Ruby August – Peridot September – Sapphire October – Opal November – Topaz or Citrine December – Turquoise or Zircon
Biwa pearls are freshwater pearls from Lake Biwa in Japan. These irregularly-shaped pearls are smoother and more lustrous than most other freshwater pearls.
BLACK HILLS GOLD
Black Hills gold is gold jewelry that is made (but not always mined) in the Black Hills area of South Dakota, USA. Gold was first discovered in that area about 1874 by Horatio N. Ross. E.O Lampinen opened the Black Hills Jewelry Manufacturing Company in Deadwood, South Dakota in the early 1900’s. Modern day Black Hills jewelry often has a three-color (yellow gold, pink gold and green gold) grape leaf and vine pattern. There are many companies that make Black Hills jewelry today, but by law, their creations must be made from Black Hills gold. This jewelry is often (but not always) 10 Karat gold.
Black moonstone is a type of labradorite and not true moonstone.
Black opals are a valuable type of precious opals with a dark ground color. They are luminous, iridescent, and frequently have inclusions of many colors (“fire”). Opal is a mineral composed of silica (and some water) and is a species of quartz. The rainbow-like iridescence is caused by tiny crystals of cristobalite. Many opals have a high water content – they can dry out and crack if they are not cared for well (opals should be stored in damp cotton wool). Opals have a hardness of 5.5 to 6.5 and a specific gravity of 1.98-2.50. Black opals are found in Australia.
Black pearls (also called Tahitian pearls) are dark-colored pearls. They are produced by the large, black-lipped pearl oyster Pinctada margaritifera (also called the Tahitian black pearl oyster), a mollusk found in the tropical Indo-Pacific Ocean. Black pearls come in many colors, including many body shades and overtone tints including gray (light gray to almost black), peacock green (especially valuable), aubergine (eggplant), and deep brown. The color of the dark nacre is determined by the minerals in the oyster’s diet (plankton) and in its environment. Many “black pearls” are dyed or irridiated to enhance or change their color; it is difficult to tell a natural pearl from a treated pearl. Tahitian pearls are graded on six factors: 1.Shape (round is most valued), 2.Size (the larger the better), 3.Surface Quality= (clean is superior to blemished), 4.Luster (the more high-gloss luster the better), 5.Nacre Thickness (thicker is better and longer lasting), and 6.Color (overtones atop the body color add value to the pearl. The most sought-after color is peacock green and darker colors are more valuable Overtone colors include blue, pink, gold, silver, aubergine, and peacock green).
BLACK STAR DIOPSIDE
(BLACK STAR OF INDIA) Black star of India is another name for Black Star diopside (CaMgSi2O6), an opaque black gem with a white, four-rayed star (an asterism). It has a hardness of 5.5 and a specific gravity of 3.3 – 3.6. These stones are found mostly in India. Stones are generally cut cabochon and are not enhanced.
Bleaching is a process in which a gemstone’s color is removed using a bleaching agent.
A flaw (blister or spot) on the surface of a gem.
An expression popularized by the hip-hop culture, used to describe sparkly jewelry, accessories and/or gemstones.
A blister pearl (also called a bouton pearl) is a pearl that developed attached to the inside of a mollusk’s shell. This type of pearl must be cut off the shell, and is therefore hemispherical. Because of their shape, blister pearls are mostly used for earrings.
Bloodstone (also called heliotrope) is an inexpensive type of chalcedony that is green with red highlights (caused iron oxide). Bloodstone is porous and relatively soft.
Blue diamonds are rare, fancy diamonds and are quite valuable. Diamonds are precious, lustrous gemstones made of highly-compressed carbon; they are one of the hardest materials known. Diamonds have a hardness of 10, a specific gravity of 3.5, and a refractive index of 2.417 – 2.419.
Blue gold is gold with a bluish tinge. It has been alloyed with a mix that includes iron.
A bodkin is a heavily jeweled, Renaissance era hairpin.
A style of jewelry and clothing exemplified by flowing lines, natural materials, and funky details. Bright colors, layers, and casual pieces are hallmarks of the Boho style.
A “Bohemian diamond” is not a diamond at all, it is actually a rock crystal.
A Bohemian ruby is actually a pyrope garnet (and not a ruby at all).
BOLT RINGA bolt ring (also known as a spring ring) is a hollow circular metal fastening ring with a spring opening. It is used to attach two other rings or links of a necklace or bracelet. The bolt ring was invented early in the 1900’s
Bonding is a process in which a colorless bonding agent (like plastic) is applied on and into a porous gemstone to make the stone more durable and have an enhanced appearance.
Bone is animal bone, carved to make beads, pins, bangles, etc. It superficially resembles ivory, but has a less-complex characteristic internal patterns and a yellower color.
A bookchain is a metal chain with rectangular links of folded metal, each of which looks like a little book. This style dates from the Victorian Era, when these chains held lockets.
Bort is a term for industrial grade diamonds.
Botanical gems are minerals that form from plants or plant material. Some botanical gems include amber (fossilized tree resin), coconut pearl (a rare, shiny, calcareous, pearl-like mineral that forms inside the coconut, Cocos nucifera), and pearl opal (also called Tabasheer opal, which form in injured bamboo joints).
A bouton pearl (also called a blister pearl) is a pearl that developed attached to the inside of the mollusk’s shell. This type of pearl must be cut off the shell, and is therefore hemispherical (half a sphere). Because of their shape, blister pearls are mostly used for earrings.
Square metal links are connected to form a smooth, even chain. Often used for men’s jewelry.
A bracelet is an ornament worn wrapped around the wrist. Types of bracelets include solid and hinged bangles, expansion, cuff, beaded, charm bracelets, Yurman-style and, and link bracelets.
Brass is a metal alloy containing (at least 50%) copper and zinc.
A Brazilian chain (also called a snake chain) is a metal chain made up of a series of small, linked cups.
White light reflected up through the surface of a diamond. Brilliance is maximized by cutting a diamond to the correct proportions.
Brilliant cut stones have 56 facets, 32 facets are above the girdle, 24 are below. Most modern-day diamonds are brilliant cut since it maximizes the amount of reflected light from the stone (its natural fire). The brilliant cut was introduced in the 1600’s.
A briolette (or drop cut) is a pear-shaped cut gemstone with triangular facets on top. This type of stone makes a nice pendant.
A brooch (also called a pin) is an ornament that can be pinned to a garment. The pink rose brooch above was made by Trifari.
Bronze is a metal alloy containing (at least 60%) copper plus tin and other metals.
A brushed finish on a metal’s surface is made by rubbing a stiff metal brush across the surface of jewelry, slightly reducing the metal’s reflectivity.
Bruting is the first step in cutting a diamond. Bruting involves shaping the girdle, which gives the stone its basic shape.
Bubbles are spherical or tear-shaped bubbles of gas captured in glass stones. Bubbles can also be found in resins (like plastics and amber), and much less-frequently in minerals (like quartz, emerald, and topaz). Looking for bubbles is one way to determine if a gem is glass or a gemstone.
A bugle bead is a long, thin, tube-shaped glass bead.
A bulla is an ancient Roman pendant that consists of a rounded container holding an amulet (a good luck charm). The bulla is worn on a strap around the neck.