Gold has fascinated and held mans attention since before the dawn of civilization. Gold was known to and prized by humans in prehistory. Because gold occurs in its native form it may have been the first metal used for rituals and adornment. Gold objects have been found in the archaeological digs of the very earliest of known civilizations dating back more than 5000 years. Gold has always been used as a standard of value. As early as 1500BC gold was already a standard medium of international trade and the earliest known coins (gold) in the world date from around 670BC. In 1922 the undisturbed tomb of the young pharaoh Tutankhamen was discovered; inside archaeologists found the largest collection of gold and jewelry in the world. The treasure of Tutankhamen demonstrated the very advanced state of craftsmanship and goldsmithing techniques of the Egyptians in the second millennium BC.
Alchemy was the attempt to turn ordinary substances, such as lead, into gold. It was believed that the right interaction with a substance called the “philosopher’s stone” could produce gold. Although alchemists failed in their attempts, they did create an interest in how substances interact, leading to the birth of the modern science of chemistry.
Long before the Spanish arrived in the new world the Pre-Columbian cultures of the Americas where producing amazingly sophisticated gold objects and had mastered the most challenging gold working techniques. Much of the Conquistador's interest in exploring the Americas was driven by stories of the incredible gold jewelry and ornamentation displayed by the Native American societies of Central America. Regrettably the Spanish melted down much of the gold objects they took and what we know of these peoples skill as goldsmiths comes from more recent excavations of grave sites.
During the ninetieth century the expansion of the western territories of the United States was accelerated by the discovery of gold. Although many western states had gold rushes the most remembered is the 1848 discovery of gold at Sutter’s Mill in California. When ever gold was discovered thousands of settlers risked life and limb to make long and dangerous journeys through what was then wild territory to reach the gold fields.
• Most all the gold ever mined is still in circulation in one form or another.
• Estimates suggest that all the gold in the world that has ever been refined would create a cube only 66 ft. a side.
• Gold is very rare. It makes up only five ten-millionths of the earths outer crust.
• Gold is the most ductile (drawn into a wire) and the most malleable (beaten into a sheet) metal known. A single once of gold can be beaten into a 300 square foot sheet. Gold can be drawn into a thread fine enough for embroidery.
• Pure gold is only slightly harder than your fingernail.
• Gold is more that nineteen times heavier than water.
• Gold is one of only two metals known that have a color other than white. Copper is the other.
• Gold does not rust, tarnish or corrode.
• Gold does not react with most chemicals. Exceptions are: chlorine, fluorine, aqua regia and cyanide. Gold will also dissolve in mercury.
Pure gold is so soft it can not withstand the abrasions of everyday wear. As a result gold is often alloyed with other metals to give it strength and durability. Common alloy metals are silver, copper, nickel, zinc and at times platinum or palladium. The amount of pure gold in an alloy is stated as either its karat or its fineness. The karat of a gold alloy is stated as the number of parts of pure gold out of 24. The fineness is stated as the number of parts of pure gold out of 1000. To give an example: 14k gold is fourteen parts pure gold and ten parts other metals for a total of 24 parts. The same 14k alloy may also be described by its fineness of 585 or five hundred and eighty five parts pure gold and four hundred and fifteen parts other metals for a total of 1000 parts, or approximately 58% gold.
Fineness Karat % Gold
990+ 24 100
916 22 91.67
750 18 75
585 14 58.3
375 9 37.5
Pure gold’s color is a rich, deep, soft, shinny yellow. When gold is alloyed with other metals not only does its strength and durability improve but its color changes as well. As a general guideline yellow gold alloys have equal mounts of cooper and sliver mixed with the gold. A warm pink or reddish color can be achieved by increasing the percentage of copper in the alloy creating “pink” or “rose” gold. A subtle green tint is achieved when the percentage of silver is increased creating “green” gold. With the exception of copper all other metals will tend to “bleach” or whiten color of gold when added to the alloy.
White gold was originally developed in the 1920s as an alternative to platinum. In recent years, due to the cost of platinum, white gold alloys have been gaining increasing popularity. White golds are not some different type of gold but true gold alloys, which have had most of the yellow color bleached out by the careful choice of alloy metals. There are two basic groups of white golds; those alloyed with nickel and those alloyed with palladium (or platinum). Both nickel and palladium (and platinum) are strong “bleachers” of gold with silver and zinc having less impact on color. Nickel white gold alloys tend to very hard and difficult to work while palladium or platinum white gold alloys tend to be very expensive. For economic reasons most commercial alloys of white gold tend to have a high percentage of nickel.
The high percentage of nickel in white gold alloys can lead to allergic reactions in some people, especially women. In response to this problem there are new nickel free white gold alloys being marketed that are using manganese as the bleaching metal.
There is no legal or industry standard (although one is being discussed) as to what constitutes a “white color” in white gold alloys. The lack of any clear standard along with the balancing act of color, cost and workability has lead to a wide range of colors in individual white gold alloys, many of which have a yellowish to brownish tint to them. The poor color of many white gold alloys has lead to the industry practice of plating the jewelry with rhodium to improve its appearance. Rhodium (along with palladium) is a member of the platinum family of metals and has a beautiful white color and wears well. Depending on the type of jewelry and how often it is worn, rhodium plating will last from just a few months to several years. Because the rhodium plating of white gold jewelry is so wide spread and rarely disclosed by the retailer, many consumers equate the color of rhodium to that of white gold. This often leads to confusion and dismay when, as the rhodium plating wears, their jewelry seems to be turning an “off-white” color. White gold jewelry can be re- rhodium plated. Re-plating requires the jewelry to be completely refinished and polished; a process that can diminish details and accelerate wear due to the abrasives used. Because small amounts of metal are removed each time jewelry is refinished it is recommended that re-plating be done only infrequently.
David West Nytch CGA www.westandcompany.com
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