Home Page” treasured stones”, a glossary of gemstones

” Treasured Stones”, a glossary of gemstones

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    Gemstones have always fascinated human beings it seems.

Stones are found in a wide variety of chemical composition, in an array of colors and in a range of hardness from 2 to 10 and may be anything from opaque to translucent to transparent, and sometimes all three.

“A Rainbow of Chipstrands”, each a continuous 30+” strand, shows the array of colors  to be seen among the stones listed below.  These gemstone chips are what remain when “rough” is  cut  into the  myriad of shapes of beads available today; round, oval, square, rectangular, triangular and tubular, both square and round.  The beaded strands may be transparent or opaque and the usual length is 35”.  They are attractive worn singly or severally, in one color or combined with various other colors to complement the colors in the clothes worn.

I also combine them with pearls or other shaped beads.  The variation in textures makes an interesting effect.  One can be easily twisted to  form a choker, or two together as shown in the photo, and held by a brooch or a connector, such as the heart shaped ones I make in Sterling. This gives a second way of wearing the strands, from a casual to a more dressy look.

To help you find and see each stone in the “rainbow”, I have listed them in order below, starting on the left with the reds and purples, through the blues and greens, ending with the yellows and neutral colors.

Rose Quartz,  Tourmaline, Rhodonite, Garnet, Amethyst (lavender, lilac and purple), Fluorite, Blue Topaz, Lapis Lazuli,  Blue Crazy Lace, Blue Moonstone, Aquamarine, Apatite, Turquoise, Amazonite, Aventurine,  Malachite, Ching Hai, Peridot, Multistrand of 4 transparent colors, Fancy Jaspar, Olive Jade, Yellow Jaspar, Citrine, Tiger’s Eye, Smoky Quartz, Natural Mother of Pearl, White MoP (30″), Rock Crystal (clear and frosted) and Black Stone (30″). 

Prices range from $25 (Rock Crystal) to $65 (Citrine, Lapis & Malachite) .  

                                 

 DESCRIPTION of TREASURED STONES I USE

 AGATE is a form of CHALCEDONY (cal-ced´-on-y) with distinctive microscopic crystals. It is characterized by bands of different shades and translucence, bands that can blend into clouds and the frilliness of BLUE LACE, or forms that mimic organic materials as in MOSS AGATE.

AMBER is a fossilized tree resin native to only a few areas of the Earth, southern China, the Baltic region and the island of Dominican Republic. It ranges in color from honey yellow to brownish orange. Amber, one of the few organic gem materials, is soft, 2+ on the Mohs. The Chinese word for amber means “soul of the tiger” and legend states that “when a tiger dies, its spirit enters the ground and becomes amber. It is the symbol of courage and fortitude. Amber is also used in Chinese medicine to give strength.

AMAZONITE is usually an opaque silicate form of Feldspar that is a pale greenish-blue in color. It in 5-6 degree of hardness on the Mohs and sometimes includes small areas of brownish iron oxide stains. While it is found in Brazil, it is also present on several other continents including the part of Russia where the legendary female warriors were said to roam, giving some the idea that the stone was named for the Amazons, not the South American River.

AMETHYST is a usually transparent purple/violet stone. It ranges from lavender to deep lilac – sometimes having white bands which even have occasional chevron angles. Unusual! Small amounts of several minerals account for its color and for that of its “cousin”, CITRINE, both Quartz based. The two sometimes appear together naturally in the stone AMETRINE, a rarer and more expensive stone.

APATITE is a transparent turquoise gemstone which has a hardness of 5. Strangely, its chemical properties are found in bone and tooth enamel. While large quantities are mined for fertilizer since it is a phosphate based mineral, gem quality crystals do occur and are rare.

AQUAMARINE is a variety of beryl with a Mohs hardness of of 7.5+. Its color ranges from a barely blue to a pale sky blue with the darkest and clearest being most valuable. It is mined in Brazil, Madagascar, Russia and the USA. Lower grades are translucent and even opaque, also ranging in color and sometimes marked with brown inclusions.

AVENTURINE is a pale to dark green translucent stone, sometimes mistaken for Jadeite. It is a form of Chalcedony and sometimes has tiny dark green specks in it.

AZURITE is named for its intense blue color, with a hardness of only 3-4 on the Mohs Scale of Hardness. It is one of the opaque stones often found near copper deposits throughout the world, along with TURQUOISE, EILAT, CHRYSOCOLLA and MALACHITE. In fact, it is the product of the weathering/oxidation of Malachite.

CARNELIAN is a pale to deep reddish orange quartzite and is a form of Chalcedony. It is almost always translucent. It has been used in China and Egypt for many centuries. Usually the darker stones come from Africa and the paler ones from Asia.

CHRYSOCOLLA is very soft and crumbly but a beautiful blue-green color. When it is becomes “agatized” in chalcedony quartz, it is as durable and hard as 7 on the Mohs Scale and is called chrysochalcedony. Druzy Chrysocolla occurs when tiny crystals form on the surface and add sparkle to fabulous color (please see Druzy Chrysochalcedony in Matrix – Brooch ).

CHRYSOPRASE is the rarest form of Chalcedony and is therefore harder that Jadeite, which it resembles because of its apple green color. It is also more expensive. Its color is due to the presence of small quantities of nickel.

CITRINE is a transparent quartzite stone, ranging from brandy colored to a medium orange to pale yellow. (see AMETHYST above)

CORAL is a rock-like deposit consisting of calcareous skeletons of marine organisms, so, like PEARL and AMBER which are also organic rather that mineral based, is fairly soft. It registers 3.5 on the Mohs and is easily worked with simple tools. Its colors vary from white to red to black, depending on the minerals nearby.

EILAT is composed of a beautiful assortment of opaque blue-to-green gemstones found near copper deposits where the mineral’s chemicals became part of the stones (see AZURITE above). Eilat is found in Israel and has not been exported for decades. Mining recently has been authorized at the Timna Mine, a copper mine near the town of Eilat that is being worked again. This mine was called the King Solomon’s Mine.

FLUORITE is prized for its glassy luster and rich variety of colors. It comes in a rainbow of colors as well as a colorless variety. It somewhat soft (4 on the Mohs) and some pieces are fluorescent and/or phosphorescent. It is sometimes mistaken for TOURMALINE, though it is very much softer and much less expensive.

GARNET occurs in a range of purplish tones, usually the warm color of a good Burgundy wine. Less commonly, it has a cooler tone and can be more expensive. It is the stone referred to as CARBUNKLE in the Bible. A green stone of the same mineral makeup is called TSAVERITE. They both have a Mohs of 7-7.5.

HEMATITE is an iron-based stone that naturally forms hexagonal crystals and its ore is the basis of the massive deposit of iron near Lake Superior. Some of the stones are magnetic. Its natural shininess makes it a   good addition to jewelry that uses less shiny semi-precious stones. It also is great used alone!

JADE (nephrite and jadeite) is stongly associated with China. There, for millennia, NEPHRITE was mined in Siberia and the west of China. It has a silkier appearance than Jadite, is slightly softer (6–6.5 on the Mohs) and is in a more limited range of colors; the translucent white called “mutton fat” to a variety of pale to deep greens (“spinach green”), that may sometimes appear together, sometimes a bit of naturally occurring iron may add yellow or russet. JADEITE is slightly harder (6.5–7) and therefore is more difficult to carve. It has a wide range of colors, adding blue, lavender, purple and pink to those of Nephrite. It comes from Burma and was not commonly used in China until the late 18th century.

JASPAR is another quartz based CHALCEDONY. It is found worldwide in an amazing array of colors, ranging from the pale sandy background of PICTURE (or WOOD) JASPAR to the dark green and red of a BLOODSTONE. Though the stones may be a solid color, the patterned stones are truly dizzying, from the spots of the LEOPARD JASPAR or POPPY JASPAR to the stripes of TIGER’S EYE or the jumbledness of RUIN JASPAR.

KYANITE is a stone that typically forms thin narrow crystals whose hardness varies according to whether it is tested across or along the crystal. It splinters but can be smoothed.

LABRADORITE is another Feldspar, this time with a hardness of 6–6.5. It is a stone that appears to be an uninteresting translucent gray. Then, when it is seen from a different angle, it may flash a plane of blue or green light. This unusual quality is shown to advantage best when worn, so that the movement of the wearer moves the stones and causes the colors to appear intermittently, here and then there.

LAPIS LAZULI is a rock composed of lazurite, the beautiful blue mineral that gives it its name, but may have inclusions of pyrite, calcite or other minerals which will lower its value and therefore its cost. It has a medium hardness (5-5.5 on the Mohs) and the best Lapis comes from Afghanistan and Tibet. It is another stone that has been used since ancient times.

LODOLITE is a transparent stone with the palest tint of red or yellow-green. Some stones may have a wisp of ivory, but that merely serves to identify it as an authentic mined stone, not a glass imitation. It has the hardness of quartz.

MALACHITE is an opaque green stone with a hardness of 3.5–4 (please see AZURITE). The most desirable has pale green or white banding across the darker green stone. Sometimes it may even have spots, though rarely.

MOONSTONE has some of the allure of Opal in a more durable and more readily available stone. It is a Feldspar and is commonly found in granite as opalescent and pearly orthoclase. Moonstone with its fascinating glimmer is at its loveliest when it flashes blue and it is then called ADULARIA.

OBSIDIAN is volcanic glass. Some breaks easily but snowflake and mahogany OBSIDIANSdo not.

ONYX is a black quartzite stone, when banded with white it is called “ZEBRA STONE”.

OPAL is a stone with mysterious beauty. It may vary from a perfect iridescent “drop of water” to what appears to be a “fractured rainbow”. Sometimes a lapidarist may choose to leave some of the matrix (the surrounding opaque stone), which creates the illusion of a view into a private miniature underwater cave. Indeed, Opals are water-formed in soft volcanic rock and some experts do advise letting an opal sit in water occasionally to refresh the intensity of the colors. It has only the hardness of 5 and can be easily damaged. An opal may sometimes be called a doublet, which means it has been glued to a harder, dark stone to heighten the play of color in the stone or when covered with a transparent material, a triplet. The resulting stone is usually set in jewelry so the back of the stone cannot be seen.

PEARL is an organic gemstone naturally formed when an irritating bit of sand, perhaps, is covered with many layers of nacre, resulting in a lovely jewel prized by royalty for millennia. Today, the irritant is often a bit of shell, rounded or shaped into a variety of forms. Imitations have often been attempted, some more successful than others.

PERIDOT is a clear yellowish green stone (Olivine) with a hardness of 6.5-7. It is the stone called CHRYSOLITE in the Bible. It occurs occasionally in meteorites.

RHODOCHROSITE is a beautiful stone formed in limestone caves when the mineral manganese colors stalagmites and stalactite a pale to deep pink. It is relatively rare compared to mined stones and therefore more expensive than most. It has a hardness of only 3.5–4.

RHODONITE is another stone colored by manganese but with the hardness of 5.5-6.5. It is more often than not marked with black lines.

ROCK CRYSTAL is colorless and transparent, pure QUARTZ. The Chinese name for it is “water essence”. It considered a symbol of sacredness and perfection, with the ability to ward off evil and bring good luck. If it is used in a bracelet, care must be taken to not let it drop or hit against a hard surface.

ROSE QUARTZ is semi-transparent to translucent in a delicate shade of cool pink. It is sometimes dyed but is usually with such a poor attempt at adding color that even an inexperienced eye will reject the resulting stone.

RHYOLITE is a spectacular combination of several minerals, each stone a work of art in my opinion. It may include some opaque warm greens, a bit of yellow or orange and often some translucent agate or even OPAL since both are of volcanic origin. It has a hardness of 7-7.5.

SERPENTINE is a major rock-forming mineral with a waxy or silky luster. It can be translucent or opaque and has a color range that includes green, yellow, brown and black. Its relative hardness is 3–4.5 on the Mohs, making much easier to carve than jade, which it has often been substituted in place of.

TIGER’S EYE is another type of Chalcedony but one with a striking difference; it is chatoyant. The crystals are arranged so as to reflect light in a striated manner, but the layers are also its weakness because if it is going to break, it will be along those lines.

TOPAZ is a transparent stone that naturally occurs in yellow, pink and blue. It is often heat treated to deepen the colors, especially the blue. While it has a hardness of 8, it can split when struck, so care MUST be taken to not hit it accidentally against anything hard.

TOURMALINE is a gemstone that is available in a very wide variety of colors, missing only orange and violet. It has a hardness of 7-7.5 since it is quartzite. Approximately 95% of all Tourmaline is bluish to brownish black so when the beautiful pink and/or green crystals are found, they are prized. Sometimes the colors are side by side, but rarely the pink is formed inside the green. This gemstone formation is then aptly named “Watermelon Tourmaline”.

TURQUOISE is a blue to blue-green mineral containing aluminum, phosphorus and copper. It is opaque with a glassy to waxy surface and has a medium hardness of 5 – 6. It is also porous and very sensitive to heat, chemicals and even body oils, therefore most of it is “stabilized” which seals and protects it from color change. Recently, scrap pieces left over from the making of round beads have been pulverized and reconstituted into shapes. It is another stone used since very early times. It is related to several other stones such as AZURITE, EILAT, CHRYSOCOLLA and MALACHITE.

This information has been compiled from a variety of sources. Several websites include both the scientific information about stones, such as what I have given above, but also their lore, believed by some to be useful for strengthening/healing. One such site can be reached at www.mineralszone.com/gemstones .