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Diamond Solitaires
Diamond weights are approximate, actual weight may vary as follows:
Diamond weights described with a decimal fraction are accurate to within ±.01 carat. For tolerances of diamond weights described with fractions or whole numbers, use the following chart:
Weight Chart
| Nominal Weight | Actual Weight Range |
|---|---|
| 1/4 Ct | .23 to .27 |
| 1/3 Ct. | .29 to .35 |
| 1/2 Ct. | .45 to .55 |
| 3/4 Ct. | .69 to .83 |
| 1 Ct. | .95 to 1.07 |
Your Guide To Colored Gemstones
Most natural colored gemstones are treated or enhanced to intensify color, diminish imperfections or improve durability. Explained below are the most commonly used and accepted treatments for different types of stones.
Emeralds
Oiling is an ancient process used to enhance the clarity of emeralds. Oil is applied to the emerald and seeps into the fissures which reach the stone's surface. Aside from improving clarity, this process may prevent brittleness. Oiling is generally not permanent and may need to be reapplied every few years. Special care is required for cleaning, repairing or mounting oiled stones. For more information, please ask your Ben David Jewelers Sales Associate.
Other Stones
Heating is a widely accepted enhancement process used on rubies, sapphires, amber, aquamarine, amethyst, citrine, tiger eye, tanzanite, topaz and tourmaline. This treatment improves the transparency and/or color of the stone. Since heating is generally permanent, heated stones do not require special care.
Diffusion is another method occasionally used particularly on blue sapphires. During treatment, a colorless sapphire is coated with a titanium and oxide compound and exposed to heat. This enhances and/or changes the color of the stone and does not generally require special treatment.
Irradiation is often used with blue topaz. The stone is irradiated brown and then heated to produce the blue color. Irradiated stones do not require special care.
Created Gemstones
Created gemstones have exactly the same chemical and mineral characteristics as their natural counterparts, the difference is that they have been created in the laboratory. Because of this, a created gemstone is usually flawless.
If you have any questions, or would like information on other treatments used for colored gemstones, ask your Ben David Jewelers Sales Associate.
Your Guide To Pearls
Natural Pearls
A natural pearl is formed in the wild by the random intrusion of a natural irritant into a mollusk's shell, without the intervention of man. There are few natural pearls on the general consumer jewelry market today.
Cultured Pearls
A cultured pearl is also grown by nature but with the assistance of man. This patented process involves the insertion of a "nucleus" into the oyster. The oyster is then carefully nurtured for the desired type of pearl. The quality of cultured pearls varies and is judged by the pearl's luster, surface, shape, color and size. Mabe and freshwater pearls fall into this category.
Black Cultured Pearls
The black cultured pearls in our collection come from Japan, China or the South Seas. Japanese or Chinese cultured pearls are dyed black through processes referred to as "irradiation" or "French Dyeing." Irradiation involves bombarding a pearl with gamma rays which blacken the shell bead of the pearl's nucleus. A "French dyed" pearl is half-drilled and submerged in a black dye chemical. The dye moves from the inside layers to the outside layers and then takes to the calcium carbonate coating of the pearl. The color achieved is even and holds for many years.
The South Seas black cultured pearls are among the largest and most valuable pearls. They acquire their color from a black-lipped oyster found only in the South Seas. The majority of these pearls are baroque-shaped and range in color from silver gray to black, with peacock being the most valuable.
Imitation Pearls
An imitation pearl is a manufactured product composed of any material or materials that simulate in appearance a natural or cultured pearl.
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