Erindale Jewelry Costume and Fine Art Jewelry
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Explanation of Jewelry Terms
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Pearls

     Pearls are organic gemstones created by various mussels and oysters when an irritant, such as a grain of sand, becomes lodged in the flesh of the shellfish. Over time, layers of nacre are deposited on the irritant, gradually building a pearl. The terms used to describe different pearls depend upon the type of shellfish, the area where they grow, and the way in which the nacre is built up.
     Natural pearls are created when the irritant is deposited without any human interference. They may have smooth or irregular surfaces, be round or odd shapes, have various colors, and various sheens. Natural pearls are rare, and exquisite examples extremely rare, so they are very expensive. As a result, we do not use natural pearls for our wares.
     Cultured pearls are created when a shellfish is pried partway open, small slits are made in its tissue, and "seeds" are inserted. Some seeds are, like those in natural pearls, bits of grit; but more frequently, small bits of tissue from other shellfish are inserted. This has the advantage that as the layers of nacre build up, the original irritant is absorbed, creating a pearl made entirely of nacre. As in the case of natural pearls, cultured pearls come in a range of colors, shapes and quality; but since they can be made at will, they are much more common, and much less expensive. We offer a selection of costume jewelry containing cultured pearls of various sizes and quality, either by themselves, or in combination with various gemstones. Note: Saltwater cultured pearls are generally intended to be more or less round, so the seeds used to culture them are usually very small, and fairly round; the seeds used for freshwater cultured pearls are often deliberately odd-shaped, so freshwater pearls tend to have far more irregular shapes.
     Shell pearls are "man-made" pearls. They are made by the same shellfish which create natural or cultured pearls, but do not involve directly inserting an irritant. Instead, after any cultured pearls and the flesh of the shellfish are removed, the nacre which was simultaneously deposited on the inside of the shell ("mother-of-pearl") is scraped off, and using heat, pressure and various dyes, permanently bonded together. The result is a pearl which is for most intents and purposes identical to the finest cultured pearls, but at a much lower price. For instance, an exceptionally fine pearl necklace made with shell pearls may sell for a few hundred dollars. A similar cultured pearl necklace might cost thousands of dollars; and a "natural" pearl necklace of the same quality could sell for tens of thousands of dollars.
     The prices quoted above are for exceptional examples. Very high quality shell pearl costume jewelry can be sold for as little as forty or fifty dollars, so we offer a wide selection of shell pearl costume jewelry. One thing to consider in choosing a piece of costume jewelry which contains pearls is whether you want the cachet and "natural" look of cultured pearls, or the superior luster and uniformity of shell pearls. Some of our offerings use cultured pearls, others shell pearls, and in some cases both are used in different parts of the piece to provide a more varied appearance.
     Pearls may also be described by their source, or by the kind of shellfish used to create them. Saltwater pearls may be called South Sea pearls, Tahitian pearls, Akoya pearls, Nanhai pearls, or any of many other "source" names, or may simply be referred to as "saltwater" or "sea shell" pearls. Freshwater pearls are usually called just that, but may also be named after the region they come from (such as Biwa pearls).


Gemstones

     Many "gemstones" occur in almost any color and quality, either naturally or through artificial means. In addition, they may vary from exceptionally fine and therefore very expensive true gemstones, to good quality but far less expensive "working" stones for which the color, size and shape are of more importance than the specific mineral or mineral variety.
     Aquamarine is a form of beryl characterized by a pale, watery blue color. Gem quality aquamarines are transparent, brilliant stones. Decorative aquamarines are translucent or slightly opaque.
     Beryl occurs in many colors. If a pale, watery blue, it is referred to as aquamarine (which see). If a deep green, it is referred to as emerald (which see). Otherwise, it is called blue beryl, green beryl, yellow beryl, and so on. Gem quality beryl is transparent and relatively brilliant. Decorative beryl is usually opaque, but can be translucent.
     Emerald is a form of beryl characterized by a deep green color. Gem quality emeralds are relatively transparent and may be brilliant, but the impurities required to produce the deep color of the finest emeralds make them less transparent than the finest beryls of other colors. Decorative emeralds may be nearly opaque, but semi-opaque and translucent stones are not uncommon. Gem quality beryl can be artifically produced, so "artificial" emeralds exist which are of far finer quality than the finest naturally occurring stones; but because they are more common, artificial emeralds are far less expensive than naturally occurring ones.
     Howlite is a powdery white mineral commonly found in association with turquoise, and chemically related to it. Its commercial use involves binding it with resins and dyes to produce "stones" of any color, shape and texture. Because of its association with turquoise, howlite is often made to look like turquoise, and most inexpensive turquoise is not turquoise at all, but colored howlite. Although that use of howlite is sometimes abused, accurately described howlite is a perfectly acceptable material for costume jewelry, because it is very stable and color-fast (thanks to its resin binder), and can be formed into any shape.
     In the case of jade, not only the colors can vary, but even the mineral. Jadeite, nephrite, serpentine and several other minerals may be called jade. Naturally occurring jade occurs in many colors, not just green, which surprises many who are familiar with "jade" only as the name of a deep green color. Yellow, white, black, pink and purple jade are among several colors which occur naturally. In addition, since some jade is slightly porous, a host of colors can be achieved by dyeing the stones. Since even natural jade involves so many colors and minerals, the value of jade depends more on the way it is handled than the nature of the stone itself. Museum-quality jade generally consists of carvings whose value depends almost exclusively upon the intricacy and quality of the carving. There is also some jade of exceptional quality which is valuable simply because of its color, but most jade beads and pendants are used in costume jewelry strictly for their decorative value.
     Lapis lazuli is a deep blue stone, and in fact sometimes so deep a blue it appears nearly black. It usually contains small inclusions, such as pyrite, which produce flecks or lines of brighter color. Good quality lapis is always opaque.
     Malachite is a greenish mineral which generally exhibits swirls, lines and twists of lighter and darker green. Malachite is usually highly polished to give it a brilliant sheen and enhance the depth of its color. It often occurs with other minerals of only slightly different chemistry, such as azurite, which has a brilliant blue color. Mixtures of high-quality malachite and azurite may be more attractive than pure malachite, and command correspondingly higher prices. Good quality malachite, whether on its own or mixed with other minerals, is always opaque.
     Ruby is a red form of corundum. As in the case of emeralds, deeply colored rubies are usually less than perfectly transparent, but such stones, though rare, do exist. Decorative rubies range from a pale red to a brilliant red, and from translucent to opaque. Gem quality corundum can be artifically produced, so artificial rubies exist which are of far finer quality than the finest naturally occurring stones; but because they are more common, artificial rubies are far less expensive than naturally occurring ones.
     Sapphire is any color of gemstone corundum save red, which is called ruby (which see). If the sapphire is blue, it is simply called sapphire. If any other color save red it is called by its color, such as yellow sapphire, white sapphire, green sapphire, black sapphire, and so on. As with rubies, the most deeply colored sapphires tend to be less transparent. Decorative sapphires are usually translucent if a paler color, and opaque if a deeper color. As in the case of rubies, there are artificial sapphires, but despite their superior quality such stones are less valuable than "natural" sapphires.
     Topaz can be almost any color. As a result, it is described as yellow topaz, white topaz, red topaz, and so on. As with most other minerals, gem quality topaz is transparent, while decorative topaz is usually translucent and not infrequently more nearly opaque.
     Unakite is a metamorphic rock (a type of granite altered by heat and pressure), originally found in the Unakas Mountains in North Carolina. The rock consists of a more or less random intermingling of green or dark green epidote, pink or salmon colored orthoclase feldspar, and (usually) colorless quartz, which produces an interesting interplay of color and pattern. Unakite is always opaque.


Lampwork Glass

     Lampwork beads, focal beads and pendants are made of handcrafted glass. Various colors of glass are melted and fused together to create artistic decorations, then annealed to give them sufficient strength to use in jewelry. Although it is possible to create similar lampwork beads, no two are likely to be exactly the same, so small variations in size and pattern are considered normal. Some lampwork glass is relatively inexpensive, but dichroic and other specialized glasses are expensive; and because of the time and effort required to create complex pieces, even beads made of inexpensive glass can be costly. In fact, lampwork glass created by skilled artisans is among the most expensive materials used in costume jewelry -- but also among the most beautiful.
     Being glass, lampwork is inherently fragile, and some care must be taken to avoid damaging such jewelry. A necklace may survive being dropped several times without any damage, only to have one or more beads shatter the next time it is dropped. (Beads which are compact are more likely to survive being dropped, while complex structures are more likely to be damaged.)


Metals

     For precious metals such as silver and gold, various techniques are used to reduce the price, and allow for their use in costume and fine costume jewelry. One method is to reduce the concentration of the precious metal. For instance, 24 karat gold is pure gold, while 12 karat gold is only half gold, and typically costs only half as much. Another method is to have only a thin layer of the precious metal on the surface of a baser metal. For instance, gold- or silver-plating involves electrically depositing a few thousandths of an inch of the precious metal on a surface. Unfortunately, such thin layers tend to wear off fairly quickly; as a result, although "costume" jewelry may involve the use of silver- or gold-plated fittings, "fine" jewelry more frequently relies on solid or "filled" metals. Filled silver or gold use layers ten to twenty times thicker than plated metal, and as a result last for many years, or even a lifetime. Filled silver and gold are created by using heat and pressure to permanently bond a thin layer of the precious metal to a baser substrate. The resulting sheets are then formed into jewelry fittings and wires. Filled gold and silver are described by the ratio of precious to base metal. For instance, 1/40 silver-filled earrings have a layer of silver thick enough to comprise one fortieth of the total weight of the metal. 1/20 gold-filled earrings have a layer of gold thick enough to comprise one twentieth of the total weight of the metal. 1/40 "filled" metals wear far better than plated metals, but if deliberately scratched, or if worn for many years, will show their true nature. 1/20 filled gold or silver items appear solid even when scratched, and if properly cared for, should last a lifetime.
     Copper, brass, bronze and similar non-precious metals are generally made of more or less pure sheets or castings of the respective metals or alloys.
     Tibetan silver is one of several materials used as a silvery or grayish substitute for silver, in much the same way as pewter. Unlike pewter, which is relatively dark, Tibetan silver has a relatively light color, hence its name (at one time it actually contained as much as 30% real silver, but those days are long gone). Tibetan silver more than four or five years old may contain substantial amounts of nickel and lead. However, all Tibetan silver on this site is a lead and nickel free alloy of zinc and copper, and contains no significant amount of any other metal. "Silver" Tibetan silver contains about twice as much zinc as copper, while "golden" Tibetan silver contains about twice as much copper as zinc. The presence of copper means that under certain circumstances the material will darken with age, but since it is the same material all the way through, its appearance will not significantly change with wear. Tibetan silver is usually used to make cast beads and fittings, in the same way as pewter. It is also sometimes plated with other metals. As in the case of other plated metals, plated Tibetan silver wears well when used as spacers and decorative beads that do not actually touch the wearer; but rubbing of surfaces that touch the wearer will eventually remove the plating.
     Earrings represent one use of metals in which the nature of the metal is not as important as the body's reaction to it. Many people are sensitive to various metals (especially nickel, hence the importance of Tibetan silver being a nickel-free alloy), and even those who are not sensitive to metals worn on the skin may be sensitive to the metals in earrings, because pierced ears are often more sensitive than other parts of the body. For this reason, hypoallergenic stainless steel earrings are usually preferred to filled or solid silver or gold, and especially to plated earrings. In addition to the possibility of metal sensitivity, earrings can cause problems due to the buildup of bacteria on the surface of the ear wires. To avoid inflammation caused by bacterial infection, you should occasionally soak ear wires in alcohol, then air dry them before wear.