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Agate
A form of chalcedony, which forms from layers of quartz usually showing varicolored bands. It usually occurs as rounded nodules or veins. The composition of agate varies greatly, but silica is always predominant, usually with alumina and oxide of iron.
Agates are found in the USA, Brazil, Mexico, Africa, Egypt, India, Italy, Nepal, Germany and Asia.
Alloy
An alloy is the homogeneous mixture or solid solution of two or more metallic elements or metallic and nonmetallic elements. Bringing the metals to a molten state, under high temperatures, and fusing or dissolving them into one solid solution usually achieves the alloy. In jewelry, combining different metals is commonly done to augment the color, hardness and/or luster of the resulting alloy.
Some common alloys used in jewelry manufacture:
Common gold alloys are made by mixing gold, silver, copper, and/or other metals to produce 14K, 18K and 22K gold, white gold (gold and nickel or palladium), rose gold (gold and copper), green gold (gold with silver or silver and cadmium), and blue gold (a recent gold color perfected by only a few jewelers).
Sterling silver is a combination of 92.5% silver and 7.5% copper, while coin silver is 80% silver and 20% copper.
Brass is an alloy typically of 60% copper and 40% zinc.
Bronze is an alloy of at least 60% copper and tin or other metals.
Pewter is an alloy of low melting point metals including tin, lead, antimony, bismuth and sometimes a bit of silver or copper. U.S. manufacturers are required by law to make lead free pewter.
Neollo is a black alloy of silver, copper, lead and sulphur. It is used to fill engraving, imparting an inlaid effect after the metal is fired and polished.
Nickel silver (also called German silver) is a white metal alloy of 70% copper, 20% zinc and 10% nickel. It contains no silver. Many people are allergic to nickel and because of this, the use of nickel silver in jewelry has been outlawed in some countries.
Anneal
Metal is annealed by heating to make it workable. In the making of jewelry, precious metals become work hardened or stressed when they are hammered, forged, rolled or bent (as in fold forming) making it brittle. Jewelers sometime purchase metals in their annealed state, which may be referred to as soft or half hard. Different metals become annealed at different temperatures and jewelers look for the "color" to determine when the metal has reached its annealed state. These colors are described as bright orange, dull red and cherry red.
Bezel Set
A bezel setting is a technique of setting a stone in jewelry. The stone is held in place by first soldering the bezel, or metal ring, to the base of the piece. Next, the stone is inserted and the metal is compressed tightly around the stone.
Brass
Brass is an alloy typically of 60% copper and 40% zinc.
Bronze
Bronze is an alloy of at least 60% copper and tin or other metals.
Cabochon
A stone, which has been cut with a rounded convex surface and a flat base. It may be high domed or almost flat and can be cut in round, oval, square or freeform shapes. A cabochon has no facets. This is one of the oldest and simplest cuts. This form of cutting is most often used on stones like turquoise, lapis, opals, various forms of quartz and other opaque and semi-opaque stones.
Carnelian
Carnelian is a form of chalcedony that ranges in color from red to orange. It is a translucent stone that may contain bands of color. It is found in India, Australia, Brazil, Germany, Madagascar, Russia, South Africa, and the USA.
Chalcedony
Chalcedony, pronounced kal-sed-uh-nee, is a microcrystalline member of the quartz family. It is found all over the world and is one of the oldest stones used by humans for decoration. It has a waxy luster and may be opaque as in jasper, petrified wood, and bloodstone or translucent to transparent in agate, carnelian, or chrysoprase. In the jewelry trade, the term chalcedony usually refers to white, gray, or blue translucent stones such as "Blue Chalcedony". Other forms of chalcedony are onyx, sardonyx, petrified dinosaur bone, chert, flint, fire agate and dendritic agate.
Citrine
Citrine is a variety of quartz ranging in colors of yellow, yellow-brown, orange, dark orange-brown, reddish-brown. Citrine crystals can form together with amethyst or smoky quartz to form bi-colored quartz called ametrine.
Almost all citrine that is available on the market today is heat-treated amethyst. Natural citrine is pale yellow to pale orange, much lighter than the heat-treated material, which is dark orange-brown to reddish-brown. All of the heat-treated material has a red tint, while natural citrine does not.
Some amethyst deposits have been found where high temperatures changed the amethyst naturally to brown citrine.
Most citrine comes from Brazil, but almost all of the Brazilian material is heat-treated amethyst. Natural citrine can also be found in the Ural Mountains of Russia, in Dauphine, France, and in Madagascar.
The inexpensive low-grade amethyst is heated at high temperatures to produce the popular orange, reddish and sherry colored citrine. Darker colors are considered more valuable, including the medium golden orange and dark sherry-colors.
Dichroic Glass
A glass, which contains ultra-thin layers of aluminum, chromium, silicon, zirconium or the metal alloy titanium. The colors are almost holographic in appearance. Addition of the various elements is what produces the bold and dramatic colors. Colloidal gold may also be added. The appearance will be different depending on whether the light is reflected or transmitted.
Garnet
Garnet occurs in every color except blue and most varieties are named for their color. Rhodolite is a purplish red; hessonite is the name for an orange, cinnamon, or pinkish variety. Tsavorite is the name given to dark green grossularite. Uvarovite and demantoid are also green varieties.
Pyrope garnets are purplish red, orangey red, crimson, or dark red. Spessartite garnets range from yellow and orange through red to reddish brown to dark black/brown. Color change garnets exhibit an "alexandrite-like" effect when viewed in natural light or artificial lighting.
Gold
A precious metal that does not oxidize or tarnish as most other metals do. It has been used for over 6000 years in coins, jewelry and ornamental objects. Gold is very malleable and can be melted and cast into both small and large objects.
Jasper
Jasper is an opaque and fine-grained variety of chalcedony quartz. It is found all over the world in all colors including: red, brown, pink, yellow, green, gray/white and shades of blue and purple and is often spotted (dalmation), striped (banded jasper), and/or multi colored (picture jasper, (poppy jasper).
Karen Hill Tribe Silver: A Brief History
Opium cultivation was a major source of income for many of the hill tribes of Southeast Asia, including the Karen?s. The Thai government worked hard to eradicate this cultivation by successfully substituting it with other cash crops, such as fruits and vegetables. Early 1960's, Thailand's Royal Majesties, the present King Rama IX, and Queen Sirikit, undertook to help the Karen people develop an alternative to growing their traditional cash crop - opium. As part of a royal project, silver experts were dispatched to impart their knowledge of jewelry to Thai Karen hill tribe farmers residing deep in the mountainous jungle of Thailand.
The first generations of Karen silversmiths were taught to carefully handcraft each design from scratch, using 99% high content silver. Karen?s learned to give each design a unique appearance only seen in their own creations often representing their culture, and history. From Karen mothers and fathers to Karen sons and daughters, they have passed down their silver work skills and traditions. Along with each unique bead or jewelry, a tale to pass on to the rest of us...
Murano Glass
Murano Glass owes its particular beauty to a very complicated and skilful process, which was rediscovered by the glassmakers of Murano in the Middle Ages. Each piece is a one-of-a-kind work of art, entirely handmade in the most famous city in the world for glassmaking: Venice.
Petrified wood
Petrified wood is wood that has fossilized leaving a stone like replica of the original wood. Petrified wood is also called xyloid jasper or jasperized wood. Palmwood is a specific type of fossilized wood from ancient palm trees characterized by dark spots.
Pewter
Pewter is an alloy of tin, lead, antimony, and a bit of silver or copper. Pewter was the most widely used metal in America between the early 1700 and 1800's. The best pewter is achieved using a low lead content and a high tin content. As you would expect, U.S. pewter manufacturer's today are required to make lead free pewter. Both copper and antimony are added to the tin to make a harder metal alloy.
Precious Metal Clay (PMC)
Precious Metal Clay represents a dramatic development in the handling of precious metals. PMC consists of microscopic particles of silver or gold suspended in an organic binder to create a pliable material with a consistency similar to modeling clay. PMC can be worked with the fingers and tools to create a vast range of forms and surfaces that would be unattainable or laborious with traditional techniques.
When heated to a high temperature, the binder burns away and the metal particles fuse to form solid metal that can be sanded, soldered, colored and polished like conventional material
The principle ingredient of PMC is gold or silver, reduced to tiny flakes smaller than 20 microns in size. As a point of reference, it would take as many as 25 of these particles clumped together to equal a grain of salt.
The other ingredients in PMC are water and an organic (naturally occurring) binder. After firing, the water and binder have completely burned away so what remains can be hallmarked as .999 silver or gold. Dried out or unwanted objects can be refined just like conventional precious metal.
How Does It Work?
Under the proper conditions, crystals of metal fuse together in the same way that droplets of water run together to make larger puddles on the windowpane. In the case of metals, oxides (tarnish) that form naturally on most metals prevent this from happening. The solution here is to use precious or noble metals in their pure state. These do not readily oxidize so even at the high temperatures needed to induce fusion they remain free of coatings. This explains why there is not a brass or sterling version of PMC - short of firing in a vacuum it won't work.
Form
PMC is rolled, pressed, squeezed, layered and molded into a desired shape. Parts can be added, removed and refined as you go, making this a spontaneous and liberating process.
Fire
After it has dried, the PMC object is taken to a specific heat (This drives off whatever moisture remains, then burns the binder. At this point the PMC is a fragile porous metallic husk. At higher temperatures the particles melt into one another to form a solid dense metal. Depending on the type of PMC, this can take from 10 minutes to two hours.
Finish
After firing, the object can be handled like any other gold or silver item. It can be soldered, burnished, buffed, tumbled; plated, etc. to achieve whatever finish you want.
Quartz
Quartz is the most common mineral on earth. It is a crystalline mineral that comes in many forms, including amethyst, citrine, rock crystal, rose quartz, tiger?s eye, chalcedony (agate, carnelian, aventurine, chrysoprase, jasper).
Rutilated quartz is clear quartz embedded with golden rutile needle like inclusions.
Tourmalinated quartz is embedded with needle like inclusions of tourmaline.
Sterling Silver
Sterling is silver with a fineness of 925 parts per thousand or 92.5% silver and 75 parts per thousand or 7.5% copper. Copper is added to the alloy to increase the silver's hardness.
Turquoise
The name turquoise is apparently related to the fact that it was brought to Europe from the Eastern Mediterranean by Levantine traders, more commonly known as Turks. Its been used as a valuable ornament for ages and was used by the Egyptians thousands of years ago. The color is, of course, turquoise, but its range of color varies from green and greenish blue to sky blue shades.
For centuries, the most valuable turquoise came from Iran (Persia) but today some specimens mined in the southwestern United States compete with it. The name "Persian Turquoise" is now generally used to refer to any turquoise stone that does not have the black or brown veining commonly found in turquoise mined in the United States and used in a style of jewelry created by the American Indians.
The Aztecs mined turquoise in an area now known as New Mexico and a significant amount of turquoise comes from Arizona, California and Nevada in the United States.
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