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Guides and Charts
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Table
Normally the largest surface on a gemstone, the table is located on the crown (or top) of a faceted stone. The table may take many geometric forms, dependent on the shape and style of fashioning. On a round brilliant-cut diamond, for example, the table forms an octagon. However, certain styles of cutting, such as checkerboards, buff tops, or roll tops, do not have a table.
Table Percentage
The table percentage of a diamond represents the ratio of table width to overall stone width. Like depth percentage, the luster of the stone is directly affected by table percentage. A beautiful stone will normally have a table percentage ranging from 53 to 64 percent.
Tahitian Pearls
Setting the standard for black pearls, Tahitian pearls are some of the most popular pearls in the world. They have a gentle, velvety luster and often exhibit a strong iridescence
Tanzanite
Tanzanite is a variety of zoisite. It has naturally occurring shades of blue, green, yellow, pink, brown and khaki but virtually all gemstone quality crystals are heat treated to produce the highly valued shades of sapphire blue, amethyst and blue violet. On Mohs’ scale of hardness, tanzanite is 6.5-7. The prime source of all the world’s tanzanite is in Tanzania near Arusha. (See Tanzanite Facts.)
Tarnish
Tarnish is the undesirable dulling due to the effects of humidity, temperature and other atmospheric conditions upon certain metals.
Tassel
In jewelry, a tassel refers to decorative group of short metal threads bound together at one end and hung from a necklace.
Tennis Bracelet
A tennis bracelet is flexible and made up of matched stones or alternating matched stones.
Tennis Style
Tennis style indicates evenly matched or alternating matched stones.
Three Stone Ring
A three stone ring is a ring setting with three stones of the same shape and the center stone is usually larger than the other two. Sometimes this symbolizes the past, present and future of a relationship.
Tie Tack
A stylish way to keep a tie in place, the tie tack has a stone or ornamental on the face connected to a short straight pin that attaches the tie to the shirt.
Tiger’s Eye
Tiger’s eye refers to a golden-brown quartz cabochon that reflects the floating play of light phenomena known as chatoyancy and asterism; thus, making the stone’s appearance similar to a tiger’s eye.
Titanium
Titanium is a metal with an extremely high melting point and is part of group of other metals with high melting points known as refractory metals. Under controlled conditions, titanium is highly reactive and can be permanently colored for various decorative applications.
Toe Ring
Often worn on one or more toes, toe rings are designed to slip easily on and off the toe.
Toggle Clasp
The toggle clasp is a simple closure consisting of a ring on one end of a chain and a small bar on the other. The bar slides through the ring and then sits across, holding the two ends of the chain together.
Tone
Tone is one of four characteristics used to describe the appearance of color. Tone refers to the lightness or value of the lightness in a particular stone.
Topaz
Topaz is a gemstone found in vivid colors. Exhibiting a wide range of colors, it appears as yellow, orange, red-brown, light to dark blue, pink-red, red, violet, light green, colorless and in unusual colors such as mystic, ocean, glacier, patriot, canary, champagne, orchid, dawn, teal and kiwi. On Mohs’ scale of hardness, it is 8. Topaz has a vitreous luster and sources include Brazil (Minas Gerais), Afghanistan, Australia, Burma (Myanmar), China, Japan, Madagascar, Mexico, Namibia, Nigeria, Pakistan, Russia (Urals, Transbaikalia), Zimbabwe, Sri Lanka and the United States.
Tourmaline
Tourmaline is a fascinating mineral that can actually exhibit two or more colors in one crystal. It possesses one of the widest color ranges, reproducing every conceivable color in the universe. On Mohs’ scale of hardness, tourmaline is 7.5. It is vitreous on crystal surfaces and greasy on fractures. Sources include Brazil (Minas Gerais, Paraida), Afghanistan, Australia, Burma (Myanmar), India, Madagascar, Malawi, Mozambique, Namibia, Nepal, Nigeria, Pakistan, Russia, Zambia, Zimbabwe, Sri Lanka, Tanzania, the United States (California, Maine), Zaire, Elba (Italy) and Switzerland (Tessin).
Translucent
There are several ways a light travels through a stone. In a translucent stone, the light is diffused as it travels through stone. Translucent stones are not clear but frosted like ice. (See also transparent and opaque.)
Transparent
There are several ways a light travels through a stone. In a transparent stone, the light travels through stone with virtually no distortion. Transparent stones are clear and easy to see through. (See also translucent and opaque.)
Trillion Cut
A “trillion cut” is a variation of the brilliant cut triangular stone with 44 facets.
Triplet
Assembled opals combine natural opal with other materials. A doublet contains a slice of opal glued to common opal, glass or other material. A triplet contains a slice of opal glued between a base and a crystal or a glass top. Triplets are usually less expensive than doublets, and both are less expensive than natural opals. Triplets are great for ring stones as they have the protective coating over the opal.
Tsavorite Garnet
Tsavorite is a gemstone within the Garnet family. It exhibits a green to emerald green color. On Mohs’ scale of hardness, tsavorite is 7-7.5. It has a vitreous luster and sources include Kenya and Tanzania.
Turquoise
Turquoise is a translucent to opaque gemstone. It exhibits a range of blue and green colors from sky-blue to blue-green to apple-green. On Mohs’ scale of hardness, turquoise is 5-6. Sources include Iran (near Nishapur), Afghanistan, Argentina, Australia, Brazil, China, Israel, Mexico, Tanzania, and the United States. |
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Vermeil
Real gold that is chemically bonded to sterling silver. The finish looks great but the price is substantially lower.
Vitreous
Vitreous refers to a glass-like luster on a stone. |
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White Gold
The en vogue color of the younger generation, white gold uses silver-colored alloys (silver, zinc or nickel) to decrease the yellow tint of gold. To intensify the white luster and eliminate the slight yellow tint, white gold is sometimes plated with rhodium or platinum. |
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Y Necklace
Forming a dangling y-shape around the neck, the Y-necklace style is usually 16 to 18 inches long. |
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Zircon
Zircon is a beautiful gemstone with a high refractive index and strong dispersion. (It should not be confused with Cubic Zirconia because the two are completely unrelated.) Zircon exhibits a range of colors including yellow, brown, orange, red, violet, blue, green and colorless. On Mohs’ scale of hardness, it is 6.5-7. It has a vitreous to brilliant luster and sources include Burma (Myanmar), Cambodia, Sri Lanka, Thailand, Australia, Brazil, Korea, Madagascar, Mozambique, Nigeria, Tanzania and Vietnam. |
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