GEMSTONE JEWELRY - A misnamed Gemstone ? Not Really !

In the Lapidary and Gemstone world, nothing is exact in the names of the various stones because of languages, regions and personal observations, unless you are down at the mineral level and even then sometimes language differences can effect that basic identity. Two such gemstones that are based historically on language and today on fancy market naming, are what is called Peruvian Turquoise and African Turquoise. Neither are Turquoise, but Chrysocolla and a Japer that look very similar to Turquoise in color.
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Here we have a necklace set designed and constructed out of several different materials. We start with three large stabilized Arizona Turquoise Matrix nuggets, highlighted with white Coral rondel beads. The necklace is then completed with Sardonyx twists, Peruvian Turquoise rounds and more white Coral rondels interspersed with open globe gold plated beads and a Hook and Loop clasp. French hoo earrings with stabilized Turquoise rounds and Sardonyx dangles complete the set.

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Stabilized turquoise - Turquoise that is soft or normally referred to as "chalk" Turquoise is infused with a clear epoxy resin. This resin, under pressure, is absorbed into the rock, which permanently hardens the rock and deepens the color. Unlike the collectible natural Turquoise which deepens in color over time by gradually absorbing oils from the skin as it is worn, the colors in stabilized Turquoise are permanent. Most of the Turquoise on the market today is stabilized and should not cost as much as natural Turquoise. Stabilized turquoise can be very beautiful, and is a good buy. Because of it's hardness and consistant color, stabilized Turquoise wears much better in Jewelry.

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Peruvian Turquoise (Chrysocolla) is as old as the ancient cultures of the Incas and Aztecs. It is also known as Mesoamerican Torquoise. Peruvian Turquoise is actually "Chrysocolla", a semi-precious gemstone that comes in a wide range of appearances and colors. It is the copper in this silicate based stone which gives it the intense blues and greens. When it has been intermixed with chalcendony and or opal, it forms a stone hard enough to be cut and polished. It is in this rare form that it becomes suitable for use in high quality jewelery. A more common low grade chalky and soft chrysocolla can be dyed or painted to look like high quality chrysocolla. Beware these stones scratch easily and they look cheap when examined closely, they also lack the stunning veins seen in high grade Chrysocolla stones. Chrysocolla often can be found to have a similar colour to genuine Turquoise. It has been valued in jewelery by the Incas, Aztecs and other ancient cultures for its colour and beauty. High grade Crysacolla or Peruvian Turquoise can look absolutely stunning.

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Corals are marine organisms typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans, which secrete calcium carbonate to form a hard skeleton which is used in the production of jewelry. Currently many species of Coraals, especially reef building varities, are being considered "endangered" and are under consideration for banning for use in jewelry and other decorative uses, following in the footsteps of Ivory. Sponge Coral, however, is not on the endangered species list, plus it is a sustainable product. Sponge Coral is a farmed product and thus is not removed from the Coral Reef and does not cause the environmental damage associated with traditional corals.
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Sardonyx is a variant of Onyx or Agate in which the colored bands are Sard in shades of red rather than black. Pure black Onyx, which is truely a died black Agate, is more common and perhaps the most famous variety, but not as common as natural Onyx with its banded colors of browns, whites and black. Onyx is usually called Sardonyx when the bands of red vary all the way from a light brown to almost black. When backlighted, and the stone is not too thick, one will see a reddish glow through the stone.

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GEMSTONE JEWELRY - Substitute for a well known Gemstone !

Over the years, due to its popularity, the price paid for Turquoise keeps going higher and higher and in many cases the availability is also becoming less and less as more mining areas are depleted and have been closed. Turquoise is normally divided into four classes, and priced accordingly.

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Natural - This comes directly from the mine. It is cut shaped and polished and set into jewelry. It has no man made treatment or additives other than a polishing compound that adds to its luster. As seen to the right, a raw piece of Sleeping Beauty Turquoise from Arizona, can be beautiful with very little polishing. Most stones in this state are very close to gem quality. The coloration of natural Turquoise can darken as oils from the skin work its way into the stone over the years, especially of not properly cleaned.
Stabilized – This is a natural turquoise usually in nugget form, but does not hold a luster. It is submerged into a stabilizing compound and dried, cut and prepared for jewelry. The turquoise has not been altered. The pores of the stone have been filled with a clear resin that makes the stone usable. This process allows for diversity of shapes and possibilities in jewelry making. Color Stabilized stones are considered altered and sometimes color has been added in this process. This in not necessarily bad, but it has less value than a piece that is naturally colored. Stabilized Turquoise usually does not change color with wear.
Treated - This form of color enhancement has been used for thousands of years. It is done as discussed earlier by submerging Turquoise stones into animal fat or vegetable oil and later air dried. Normally the color will not last very long. A new variety on the market, called "Motaska" and "Majave" Stone is much more stable and retains its color as well as being infused with gold, silver and copper.
Fake and Synthetic – Ceramics, bone, celluloid and plastic are used to imitate turquoise. Synthetic turquoise has a very natural matrix that is produced by placing stones in the synthetic “batter” .

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In addition to these four classes , we also have some natural gemstones that can be colored to look like Turquoise. The best known is Howlite, but some other common Turquoise colored gemstones are Magnesite and Ivoryite. Howlite, especially, is known for being colored in many colors other than Turquoise.

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This design uses turquoise colored Magnesite barrels in line with two sizes of Carnelian round and flat beads with Sardonyx barrels. The set is completed with silver French Hook earrings with a dangle of Carnelian, Sardonyx and stabilized Turquoise flats.

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Magnesite is a compound that substitutes iron for magnesium with a complete solution series with siderite. Dolomite is almost indistinguishable from magnesite. Magnesite is normally stablized and color shot except for that which is left white or ivory in color as a substitute for Ivory. Many vendors sell Magnesite as stabilized Turquoise. Also the famous Wild Horse Turquoise sold throughout the Southwest is predominately Magnesite dug from the same mines as Turquoise and many times has Turquoise as well as other minerals mixed through it to make for the beautiful designs.

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Stabilized turquoise - Turquoise that is soft or normally referred to as "chalk" Turquoise is infused with a clear epoxy resin. This resin, under pressure, is absorbed into the rock, which permanently hardens the rock and deepens the color. Unlike the collectible natural tTrquoise which deepens in color over time by gradually absorbing oils from the skin as it is worn, the colors in stabilized Turquoise are permanent. Most of the Turquoise on the market today is stabilized and should not cost as much as natural Turquoise. Stabilized turquoise can be very beautiful, and is a good buy. Because of it's hardness and consistant color, stabilized Turquoise wears much better in Jewelry.

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Sardonyx is a variant of Onyx or Agate in which the colored bands are Sard in shades of red rather than black. Pure black Onyx, which is truely a died black Agate, is more common and perhaps the most famous variety, but not as common as natural Onyx with its banded colors of browns, whites and black.
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Carnelian (also spelled cornelian) is a reddish-brown mineral which is commonly used as a semi-precious gemstone. Similar to Carnelian is Sard, which is generally harder and darker. The difference between the two is not rigidly defined, and thus the two names are often used interchangeably. Both Carnelian and Sard are varieties of the silica mineral called Chalcedony and are colored red by impurities of iron oxide. The color can vary greatly, ranging from pale orange to an intense almost-black coloration.

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GEMSTONE JEWELRY - Go For The Look !

Many times using the colors from a highlight bead or pendant brings a necklace together as a single unit.

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This gemstone set uses a striped Sardonyx gemstone which was end drilled as the highlight of the necklace. Polished Coral rounds combines with Carnelian discs and rounds with silver highlights and toggle clasp complete the necklace. French hook earrings using the Carnelian rounds and disks with silver highlights complete the set.

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Sardonyx is a variant of Onyx or Agate in which the colored bands are Sard in shades of red rather than black. Pure black Onyx, which is truely a died black Agate, is more common and perhaps the most famous variety, but not as common as natural Onyx with its banded colors of browns, whites and black.

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Carnelian (also spelled cornelian) is a reddish-brown mineral which is commonly used as a semi-precious gemstone. Similar to Carnelian is Sard, which is generally harder and darker. The difference between the two is not rigidly defined, and thus the two names are often used interchangeably. Both Carnelian and Sard are varieties of the silica mineral called Chalcedony and are colored red by impurities of iron oxide. The color can vary greatly, ranging from pale orange to an intense almost-black coloration.

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Corals are marine organisms typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans, which secrete calcium carbonate to form a hard skeleton which is used in the production of jewelry.

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BLACK ONYX - a manmade variety of Chalcedony (Agate) !

Every now and then, a real surprise comes along and makes one step back and wonder about many other things. One such rendering took place this past weekend at the Southwest Gems and Mineral Society Show. Was told by a knowledgable lapidarist when looking at a display I had, than there isn't such a thing as "Black Onyx" which was included in several of the necklace sets I had on display. So started checking around, and the Earth Science Department from Trinity University was present with a booth, so chatted with them for a bit, and yep, no such thing as natural "Black Onyx". To make things easier to understand, here are some definitions of "Black Onyx" off of several different sites on the Internet.

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"Black onyx" is neither truly onyx nor truly black, but it is actually dyed chalcedony. According to some experts, it is produced by boiling slabs of gray chalcedony in a sugar solution. The sugar permeates the stone's "pores" between the submicrocrystallites and darkens the appearance of the stone. This dye/treatment is stable and requires no special care.

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Black Onyx - unknown in nature, it is produced by warming chalcedony in a sugar solution for several days or weeks. The stone in then placed in warm sulphuric acid. The acid reacts with the sugar, precipitating the free carbon. The black color is permanent.

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Black Onyx - Mohs Hardness: 6.5-7 - Treatment: Dyed for color uniformity - Color: clear to browns (See also Chalcedony as no such thing as Black Onyx). Onyx and Sardonyx are similar to agate, but Onyx has straight rather than curved bands. These bands may be in shades of browns, reds, tans, yellow, greens and rarely blues and will always have white. Since ancient Egyptian times, onyx has been stained to improve or change its color to an all black gemstone. All totally black onyx has been produced by soaking black agate (chalcedony)or other Onyx, especially clear, in a sugar solution, then heating it in sulfuric acid to carbonize the sugar particles. Found worldwide. Onyx is formed by the deposition of silica in gas cavities in lava, which results in the distinctive bands.

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So from now on the proper term to use with the 'little or big black stones' used in jewelry, should be either black Agate or black Chalcedony with the added comment "enhnaced by chemical treatments and is called black Onyx". One learns something new every day if you listen good.

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