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Terms, Definitions, General Information about Materials Used


Sterling Silver

Sterling silver is an alloy (i.e. a mixture) of fine silver and other metals, usually primarily copper, at a ratio of 92.5% silver to 7.5% other metal. Other silver alloys do exist, such as the 80/20 ratio found in what is often referred to as "Mexican silver" which in the US market is sometimes used in specialized applications, such as reticulation. Sterling silver (and other silver alloys) are less malleable and harder than fine silver, and therefore are the traditional choice for jewelry, tableware and other applications that must withstand wear.

Fine Silver

Fine silver is another term used to describe un-alloyed silver. Fine silver must be .999 pure, although may contain some trace amounts of other elements. With the growing popularity of precious metal clay (PMC), the availability of fine silver jewelry is increasing. In its unprocessed form, PMC consists of fine silver in a clay binder--this can then be worked into shapes and heated so that the clay burns off, leaving the shaped metal piece. Fine silver is softer than sterling silver and is therefore not suitable for pieces that will undergo some wear.

Base Metal

Base metal is a "catch-all" designation for any non-precious metal. A yellow colored base metal often used in jewelry application is brass. White base metals in jewelry can vary but may be zinc, steel or nickel. In some applications, such as electroplating, copper might be the base metal that is then plated over with a precious metal (usually used in gold plating).

Yellow Gold

Yellow gold is an alloy of gold and other metals, typically including copper and silver, that are chosen to maintain gold's yellow color when blended. The amount of gold in the alloy determines the karat of the gold (abbreviated with a "k"). Karat measurement is based on parts per 24; for example un-alloyed gold is considered 24k. If an alloy contains 14/24 gold (or a little over 58%) it is considered 14k. 18k gold is 75% gold (18/24). 24k gold is quite soft and maliable, rather unsuitable for most jewelry applications, which is why gold is typically alloyed in jewelry. Ultimately, the karat chosen in a jewelry application is a matter of personal taste, cost consideration and practical decisions of how piece will be used. 18k yellow will be softer and more expensive to produce than a comparable 14k item, but will contain more gold, and be "richer" in color.

White Gold

White gold is an alloy of gold and other metals, usually nickel, copper and zinc. Some white gold is alloyed with palladium (a metal in the platinum family) and silver, making it more easily workable, but more expensive; this gold is sometimes referred to as palladium white. With either combination, the white gold alloy gives the metal a whiter appearance than yellow gold. White gold is yellower in appearance than silver or platinum; some customers desiring a brighter shade of white opt for rhodium plating; this results in a bright white finish but one that can wear off with time. As with any gold alloy, a higher karat number indicates a higher percentage of gold.

Gold Plate

Gold plate (or electroplate) is electrochemically deposited gold over a base metal, copper, silver or a combination of layers of these metals. Basically, the electroplating process uses electric current to "attract" gold particles to the piece being plated. Electroplating deposits are in the range of 3-50 millionths of an inch thick.

Silver Plate

Silver plate refers to base metal that has been electroplated with silver. Basically, the electroplating process uses electric current to "attract" silver particles to the piece being plated. Electroplating deposits are in the range of 3-50 millionths of an inch thick.


Vermeil refers to gold that has been plated over silver. Typically, the layer of gold plated in vermeil is thicker than in other gold plating applications.

Gold Filled

Gold fill consists of a sheet of gold over (and sometimes under as well) a base of another metal, usually brass, copper or steel. The bonding may use a brazing paste or fusion welding to join the metal sandwich into sheet or wire forms. The piece is then rolled or drawn into the final shape. The gold layer may be any karat (14k, 18k, etc.) and should be indicated on the finished item. Filled items typically have a thicker--and therfore more durable--layer of fine metal than plated items.


Platinum is one of the rarest elements on Earth. In jewelry applications, it is typically mixed with 5-10% other precious metals to improve its wear resistance. In addition to its rarity, its durability and beautiful bright white color make it a highly-sought metal for use in the best jewelry. Its wear-resistance makes platinum a perfect choice for everyday-wear items, such as wedding bands, and for heirloom pieces that can be enjoyed for many years and by many generations.

Rhodium Plate

Rhodium is a member of the platinum family. It is often used to plate objects to improve their white brightness.


Copper is an elemental metal and becuase it is soft and has a pleasing red-orange color, was frequently used in ancient jewelry and other applications. Chemically-treated copper can take on a wide variety of bright and cheerful colors through patina applications and colored copper can be found in a variety of art jewerly, building applications, home goods and other decorative uses.

Green Gold

Green gold is pure gold alloyed with a percentage of silver to give it a greener overtone than yellow gold. Green gold's contrasting color makes it a popular component of mixed-metal jewelry, although it is also beautiful on its own.



Agate is a type of chalcedony (which is a type of quartz) that often occurs in banded (striped) hues. Agates can be transulcent to opaque. They form in mineral-rich water that flows through cavities in volcanic rock and can be found worldwide. Because of its porous nature, agate is sometimes dyed--any known dye process will be disclosed in the item description. A fairly durable stone, agate can be cleaned in the ultrasonic or steamed.


Amazonite, also known as Amazon Stone or Amazon Jade), is a type of feldspar that varies in green color, depending on where it is mined. It gets its name after the Amazon area of Brazil, when European visitors were given green stones that they believed were similar to those they had been familiar with from Russia. As it turns out, Amazonite is not found in Brazil, but the name stuck. Those travelers were probably given jade. Amazonite is found in Russia, parts of the US and Canada, India, and a few regions of Africa. Amazonite is sensitive to chemicals, abrasives, heat, acids, and ammonia. It should not be exposed to moist heat in any form (steaming, ultrasonic cleaning or hot water should not be used to clean it). Instead, use mild soap and room temperature tap water with a soft cloth.


Amethyst is a type of quartz with a hardness of 7 on the moh scale. It varies from light rose-purple to very deep, almost black-purple. Its name comes from a Greek word, meaning "against drunkenness." This may be due to the belief that wearing it wards off the effects of drinking alcohol, although others think it probably refers to the wine-like color of the stone. The purple color in amethyst comes from traces of iron and manganese in the stone. Its purple color is associated with royalty, and the stone has long been favored by the wealthy and powerful throughout the ages. Amethyst can be steamed and cleaned in an ultrasonic. However, avoid very high heat: kiln-heated amethyst loses its purple color and becomes citrine!


Apatite is a phosphate mineral group made up of chlorapatite, fluorapatite (used in fluoridated water) and hydroxylapatite (the major component of tooth enamel). Natural apatite comes in a wide variety of colors, most often found as blue to blue-green. The most common gem variety is translucent to transparent in the popular green-blue seawater color, making it a somewhat inexpensive, although softer and less durable, substitute for aquamarine. Coincidentally, the name "apatite" is derived from the Greek word "apate" meaning "deceit" or "to deceive." Heat treatment is often applied to improve appearance and/or to deepen color. Apatite is fragile and very sensitive to chemicals, abrasives, heat, acids, and ammonia. Do not use a steamer, hot water or Ultrasonic cleaners with this gemstone. Clean with mild soap and room temperature tap water with a soft cloth. Do not subject apatite to rough abrasion or impact.


Aquamarine gets its name from the Latin phrase "water of the sea" and aptly so as its blue-green color looks like a tranquil Mediterranean ocean. Aquamarine is in the beryl family, which is the same mineral group to which emeralds belong. In all but the most expensive and highly prized specimens, heating is used to remove yellow components to produce a purer blue color with fewer yellow/green undertones. Although this stone has a higher Moh’s rating (7.5 – 8), it is still sensitive to heat, acids, and ammonia. Use caution when using a steamer, hot water or Ultrasonic cleaners with this gemstone. If the stone has feathering or fractures it can be damaged with these cleaning methods. Use mild soap and room temperature tap water when cleaning this stone.


Aragonite is a pale yellow form of stalactite deposit named after the Aragon River in Spain, where it was first discovered. It has a soft lustre similar to pearls. Aragonite can be fragile, so it should only be washed in warm water and gentle soap. It can shatter with heavy force, so care should be taken not to jar the stone with too much impact.

Austrian Crystal

Leaded crystal that is usually faceted. Generally heavier than other glass beads and often treated with a special finish which results in a "rainbow" when lit from certain directions. The faceting on leaded crystal beads is crisper than on typical cut glass beads, resulting in more sparkle.


Aventurine is a type of opaque quartz that has a special shimmering quality, the result of mineral inclusions within the rock matrix. It is generally green to blue-green, but sometimes can be found in brown, orange or pinkish-red hues, the latter not to be confused with sunstone, a similarly shimmery rock. Aventurine, as a type of chalcedony quartz, is a fairly durable stone, so it can be steamed or cleaned in an ultrasonic if you'd like.

Blue Chalcedony

Chalcedony is a translucent to opaque variety of quartz. While several colors of quartz are actually chalcedony, typically in jewelry when one talks of chalcedony, they are referencing the white, blue to gray-blue or purple-blue hues. The differing colors or banding are due to various mineral inclusions within the stone. Pure chalcedony is white, and is easily dyed due to its porous nature. Any known dye or other enhancement treatments will be disclosed on the FabMartha product description. Chalcedony is a type of quartz, and so is fairly durable. It can be steam cleaned or put in a ultrasonic (unless dyed).


Carnelian is a red variety of chalcedony and is a micro-crystalline quartz. It has a hardness rating of 6.5-7. It has been a popular stone in jewelry making through the ages, as examples have been found dating about as early as 3000 BC in Egypt (where it was placed on mummies to aid in their transition to the afterlife), Persia and Sumeria. Romans, who believed it a stone of courage, used Carnelian in their signet rings and cameos. It is sometimes dyed to intensify the red color--any dyeing known dye process will be disclosed in the FabMartha product description. Carnelian is fairly durable. It can be steam cleaned or put in a ultrasonic (unless dyed).


Ceramics encompass a variety of materials, but in general, they are inorganic and nonmetallic material formed into usable objects and fired at high temperatures. The raw material can be clay, glass, cement, or more advanced carbides, oxides and nitrides. Ceramics have a myriad of everyday and/or high-tech industry uses, including many creative jewelry options. Ceramic can vary from the modern and durable titanium carbide to the much more delicate antique pottery shards or hand-made clay beads. They may be glazed or unglazed, the latter being more porous and typically more fragile. Unless otherwise specified, treat ceramic jewelry as you would pearls--use only a soft cloth to gently clean the piece. You may use warm soapy water on sealed and glazed pieces.


Chalcedony is a type of colored quartz. It comes in a variety of colors from the well-known blue, to violet, to pinks to rust-reds. The differing colors or banding are due to various mineral inclusions within the stone. The stone usually has a milky appearance. Sometimes it is dyed, and this process with be disclosed if known. Chalcedony is a type of quartz, and so is fairly durable. It can be steam cleaned or put in a ultrasonic (unless dyed).


Charoite is a purple, sometimes fibrous-looking, stone formed when limestone was altered by alkali-rich nephine syenite and named for the Charo River in Siberia, its only known geographic location. Somewhat rare, it was discovered in the 1940's and is a relative newcomer to the jewelry industry, being used starting in the 1970's. It is often stabilized with an injection of polymer to increase hardness. Treat charolite with care and clean only with a soft cloth and gentle soapy water if necessary.

Chrysanthemum St

This is a black and white rock made up of Gypsum clay, Dolomite and Limestone, with internal crystals of Calcite, Feldspar, Celestite or Andalusite. The inclusions resemble chrysanthemum flowers, hence the stone's name. Soft cloth cleaning, using gentle soapy water if needed, is recommended.


Citrine is a form of quartz and is closely related to purple sibling amethyst. Sometimes the two are formed in the earth together, creating ametrine. Citrine's name comes from the French word for lemon, "citron." Naturally yellow citrine is rare and demands a premium price. Most citrine that you'll see on the market is heat treated--this treatment is applied to bring out the rock's sunny yellow color. In antiquity, citrine was valued as a sun stone, though to have the ability to capture the sun's light. Its golden, sunny color was associated with gold and wealth, so it was known as a merchant stone. Care should be taken not to expose citrine to direct sunlight for long periods, as light treatment can permanently change color with prolonged exposure. It can be cleaned in the ultrasonic but do not steam clean. It is durable to use with most jewelry cleaning solutions.


Coral is the skeletal shell of a marine animal by the same name. It is fairly soft (3.5-4 on the Moh scale). Coral is usually dyed to give it its vibrant color. Some coral is reconstituted: that is, it is pulverized and then mixed with a binder to shape into beads, cabochons, etc. Any known treatments will be disclosed on this site. Coral is soft and should be gently cleaned and cared for. Use only a soft cloth and protect the material from impact.

Cubic Zirconia

Cubic Zirconia (CZ) is the crystalline form of zirconium dioxide. It is a synthetic, man-made gemstone that when faceted has similar brilliance to diamonds and is nearly as hard, although it is a bit denser and heavier than a real diamond. Manufacturers sometimes add color to CZ to mimic other precious or semi-precious stones, such as emerald, citrine, ruby or peridot. CZ's are relatively easy-care stones. They are hard and durable, and should withstand most cleaning and everyday wear processes.


Diamonds are the hardened form of carbon, formed though intense exposure to heat and pressure through thousands of years. There is much to consider before a purchase of a diamond, and several cost factors to consider (you have probably heard of the 4 C's: color, cut, clarity, carat). It is important to have a conversation with your jeweler to determine your purchase options. FabMartha is here to help walk you through all of the considerations to help you find the best diamond to suit your taste and budget. As one of the hardest stones on Earth, diamonds are easy to care for. They can be cleaned using almost any method, including in the ultrasonic, and they look dazzling after a blast from the steamer. But beware, even diamonds can chip if treated too roughly. Protect your investment by avoiding hard impact to the stone.


The well-known, striking green member of the beryl family. Most of the time, a coating of oils or polymers are applied to improve the stone's appearance. If properly cared for this treatment is permanent. Emeralds are hard (8 on the Moh scale) but brittle and subject to stress breakage. Care should be taken not to knock or jar the stone during wear. Emeralds should not be steamed or cleaned in the ultrasonic.


Flourite is a a translucent, often banded, form of calcium flouride. Beautiful variations of purple, violet, green and clear band can often appear in the same piece. Flourite is somewhat brittle, so should not be subjected to impact. It can be cleaned with soapy water and a soft cloth.


The name comes from the Latin granum for "seed-like," as it was thought that red garnets resembled pomegranate seeds. There are six common types of garnets that range in color anywhere from yellow green to deep purple-reds. Brilliant green tsavorite is a type of grossularite garnet, for example, and due to it's beauty and rarity fetches a high price. The other classifications are almandine, andradite, pyrope, sessarite and uvarovite. While the differet types vary in availablity and rarity, all are beautiful. Garnet, while fairly hard (7 to 7.5 on the Mohs scale) can chip, particularly when bumped against other garnets, so care should be taken not to subject them to impact. All garnets but green varieties can be cleaned in an ultrasonic, but steaming should be avoided as high heat can change the stone's color. Harsh chemicals should also be avoided with all types.


Geodes stones that have cavities lined with crystals that have grown within them. These crystals can be made of quartz, amethyst, citrine or calcite. Because geodes often contain drusy components that could dislodge if jarred, care should be taken with your geode. Wash gently in soapy water if needed and rub only very gently with a soft cloth if required.


Glass can chip or crack with high-impact, so avoid subjecting your glass object to too much force. Most glass is easy to clean with almost any household cleaner, but do avoid subjecting coated glass to heat, rubbing or harsh chemicals.


Hessonite is a member of the garnet family and comes in ranges of browinsh to orange hues (which is why it is sometimes called cinnamon stone). It is rarer than it's red-colored counterpart. Garnet, while fairly hard (7 to 7.5 on the Mohs scale) can chip, particularly when bumped against other garnets, so care should be taken not to subject them to impact. All garnets but green varieties can be cleaned in an ultrasonic, but steaming should be avoided as high heat can change the stone's color. Harsh chemicals should also be avoided with all types.


Howlite is a soft and somewhat porous stone, looking like a creamy white marble in its undyed state. It takes dyes beautifully, so is often used to mimic turquoise or lapis with various dye treatments. Howlite is a somewhat soft stone, so care should be taken in cleaning it. Abrasives should not be used. Use only a soft cloth and gentle dish soap if needed and rise thoroughly.


Iolite, composed of corderite and cyclosilicate, appears blue to violet depending on the stone and the light. It's rich color and changeability remind one of a summer sky as dusk turns to dark. The name "iolite" comes from the Greek word "ion," meaning "violet." Iolite is fairly hard (7-7.5 on the Mohs scale), but should not be steamed or put in an ultrasonic. It is also advised that harsh chemical cleaners be avoided, although soapy water and a gentle brushing are fine for thorough cleaning.


Jade can be one of two different minerals, nephrite or jadeite. Either are correctly called "jade" although they quite different. Jadeite is white in its pure state, but formation with other minerals will lend different colors to the stone. Jadeite can range from dark green, to emerald (this color known as "Imperial Jade"), to lilac, pink, brown, orange, red, black and sometimes even blue. On the other hand, Nephrite occurs in a limited color range, from pale to dark green. In New Zealand, nephrite is known as "green stone." Since earliest times, the Chinese have considered nephrite a royal gem, and Maoris have valued nephrite's hardness and durability, as well as beauty, and have used it to fashion not only jewelry and totems, but also weapons. Similarly, jadeite has been used and continues to be used by Mayan descendants, the Olmec for a variety of ornamental and functional uses. Jade is fairly durable, although care should be taken to avoid heat and chemical exposure. If your jade has been treated with dyes or sealed with wax, you will not want to put it in an ultrasonic, but untreated jade is sturdy enough to be cleaned in the ultrasonic. If unsure, your safest bet is to use gentle soap and water to clean your jade.


Jasper is a fine-grained, opaque form of quartz rock, containing various shades of reds, browns or greens due to mineral impurities such as clay, hematite and goethite. These impurities and fracture filled inclusions give gasper incredibility interesting bands, angular fragments, spots and patterns. Jasper can be steam cleaned or submerged in an ultrasonic, unless dyed or coated. Most commercial jewelry cleaning solutions may be used with jasper, but spot check if you are uncertain.


Also known as spectrolite or "black moonstone," this stone is typically lavender-grey with flashes of blue. These iridescent flashes come from something called "labrodorescence," caused by light being defused from think layers of feldspars that settled within the stone as it cooled. While grey-blue is the most common color of labradorite, it also can be green, orange, red or yellow. It has a Mohs hardness of 6-6.5, so it should not be struck with sharp force. Use only mild soap and warm water to clean. Labradorite can be scratched so do not use abrasives.

Lapis Lazuli

Lapis lazuli is not a single mineral, but a composite aggregate rock that is colored by lazurite and containing other minerals. It often also contains flecks or veins of pyrite that provide sparkling golden contrast to its bright blue color. The name is derived from the Latin "lapis," meaning stone, and the Persian word "lazhuward" which means "azure blue." The stone has been revered since antiquity by such civilizations as the Chinese, Greeks and Romans, and was particularly valued by Egyptians, as is evidenced by its use in King Tutankhamen's funerary mask. It was also ground as a pigment for makeup and medicines, and was even used as a paint pigment until the color was finally synthetized in 1928. Some lapis used in jewelry is reconstituted (that is ground up and reformed using a polymer binder), dyed or acid-washed to intensify color; any known treatments will be disclosed in the product description. Lapis lazuli is porus and somewhat soft, so should be gently treated, cleaning with gentle soap and water only.


Lodolite is a variety of quartz with unique mineral inclusions, created over millions of years. Some strands may have some beads with golden rutile or red hair inclusions. It is a unique and interesting stone. Lodoite is a type of quartz, and so is fairly durable. It can be steam cleaned or put in a ultrasonic.


Malachite, a green stone that resembles marble, is mainly a hydrous copper carbonate compound. It is the copper content of malachite that gives it the green color, similar to the green verdigris you might find on outdoor copper fixtures. The banding and striping within the stone is due to varying amounts of water that make the copper lighter or darker. When polished, malachite has a silky luster, but resins are usually used to enhance this shine as well as protect the surface of the stone. Malachite is easily scratched and sensitive to chemicals and abrasives, heat, acids, and ammonia. Never use a steamer, hot water or Ultrasonic cleaners with this gemstone. Use mild soap and room temperature tap water with a soft cloth so you do not scratch the surface or diminish the luster of the gemstone.


Marble is a metamorphic rock composed of recrystallized carbonite minerals, most commonly calcite, dolomite or limestone. While most often used as a building or sculpting material, marble can also make striking jewelry. It comes in a wide variety of colors, with different varieties being specific to geographic locations. Marble is typically durable, so can be cleaned using most commercially available methods. If the marble surface is unpolished and/or porous, it is best to stay away from chemical cleansers and to use a gentle soapy water to clean.


This stone is the pink member of the beryl family (same family that the emerald is from).


Mother-of-Pearl is the inner layer of a mollusk shell (it's considered the mother of a pearl becuase this part of the shell is where a pearl grows from the mother-of-pearl secretions). Mother-of-Pearl is often bleached to improve the bead's whiteness. It has a hardness of 3-4 on the Moh's scale.


Moukaite is a type of jasper found in Australia. The broad patterns of red-browns and golds in this stone are due to included minerals such as clay and iron oxide.


There is much to know about pearls. They can be from fresh water or the sea, they can be cultured or natural, bleached, dyed or chemically enhanced, or untreated. It helps to get as much information as you can to best understand your purchase decisions. The pearls used in FabMartha designs are fresh water pearls unless otherwise indicated. Any known treatments will be discolosed with the item's description. The best way to care for pearls is to keep them away from heat, solvents, chemicals and abrasives. Don't put a strand of pearls on until after you've applied your hairspray. Pearls are best maintained by occassionally wiping with a soft cloth. If more aggressive cleaning is needed, special cleaning solutions specifically formulated for pearls are available.


Rarely treated with colorless Oil, Wax, Natural and Synthetic Resins into voids to improve appearance. May be heated to oxidize specific minerals to enhance color.

Plastic / Resin

Plastic can be heat-averse, so avoid steaming or other heat. It is easily cleaned wtih gentle soap and water, but chemicals can cause pitting in some types of plastic, so if you are unsure, do not use anything too agressive to clean your plastic jewelry.


Quartz stones are occassionally heated, irradiated or coated to improve color and appearance.


Rhodonite is an opaque pink to dark-pink stone that usually features marbled black inclusions. It is a good stone for spring and autumn complexions. Rhodonite is of medium hardness; to avoid damage, do not hit the stone sharply. It can be porus, so do not submerge in chemicals. Steaming or cleaning with soapy water are recommended.


Ruby (a member of the corundum family, as are sapphires) is known as the "queen of the gemstones." Ruby is considered the rarest of all gems. Rubies are often heat-treated with additives to improve color and appearance. Examples of the additives used include Beryllium (i.e. light element) to permanently improve color and Borax or Lead (i.e. glass) to permanently improve appearance. Rubies that come directly from the mine with no imperfections and perfect color are very rare indeed, so natural, untreated rubies will command the highest price. Treated rubies are durable and can withstand steam and ultrasonic cleaning. Care should be taken with untreated rubies; although they are durable, they should not be heated or they may loose their untreated color.


Although blue is the most well-known color, sapphires can range in color from whites and very pale yellows to vibrant oranges, greens and purples. Red sapphires are best known as rubies. Sapphires are a 9 on the Moh's scale, making them the second hardest gemstone (diamonds being the hardest). As with rubies, sapphires are usually heat treated or irradiated. Untreated sapphires are very rare and command a premium price. Sapphires can withstand steaming and ultrasonic cleaning. However, care should be taken not to heat untreated sapphires for fear of damaging it's color and untreated integrity.


A blue stone similar in appearance to lapis.


Heat treating is almost always applied, this producing the violet-blue colors for which the gem is known.


Irradiation is usually applied to improve color intensity or to produce unique colors.


Tourmaline comes in wide variety of colors, green and pink being the most highly prized. Blues and greens are typically ehnanced with irradiation. Most other colors are typically untreated.


Much mined turquoise is waxed, treated with resin, or otherwise stabilized for better wear resistance and improved appearance. Natural turquoise is available, and varies from inexpensive highly matrixed stones with black inclusions to rare specimens of unincluded pure bright blue (a fine example being specimens from the Sleeping Beauty mine in Arizona). Turquoise is a relatively soft stone. Care should be taken in wearing so as not to scratch or chip the gem. It should not be steamed or cleaned in an ultrasonic. Wiping with a soft cloth is the best way to clean turquoise items.


Unakite contains a blend of fall-like greens and reds. Unakite is named for the place it was discovered in South Carolina, U.S.A..