Monday, March 23, 2009
The Wonderous Green Gemstone - Peridot
Peridot is deep green stone that is often used as the focal bead in sterling pendants. Peridot and olivine both belong to the beryl family of gemstones, although the physical and chemical properties of the two stones are quite different. Peridot typically is a combination of iron silicate and magnesium silicate. Ideally, iron silicate or fayalite is less than fifteen percent. Above this content, the color of the stone can change to yellow or brown, both of which lessen the value of the stone. Facet cut stones that are less than 5 carats in weight are commonly used in fashion jewelry. The cost of the stone goes up with size. Stones larger than fifteen carats are rare and can be quite expensive. Some of best specimens of peridot today come from the Hindukush mountains near the Afghanistan – Pakistan border. This deposit, located at an elevation of over thirteen thousand feet, and was discovered in the mid nineteen nineties. The area is quite rough, and mining can only occur in the summer months after the snow has melted and the roads leading to the mines are passable.
The Allure of Topaz Jewelry
Topaz is quite famous for its stunning blue color. However, it most commonly occurs as a transparent colorless crystal. Other colors including pale blue, yellow and some times even light brown can be found in nature. Other less common colors include orange, pink, red or violet. Light that travels through the stone is bent to different degrees based on the properties of the incident light. Therefore, when viewed from different angles the stone can exhibit a range of colors. This is one of the properties that has made topaz a favorite for sterling pendants and other silver jewelry. Topaz is a hard stone, rating an eight on the Mohs scale. Topaz should not be cleaned using ultrasonic cleaners or harsh chemicals or steam cleaners. A q-tip with warm soapy water should be able to get out most grime without damaging the stone.
The Attraction of Opal Jewelry
Opal is non-crystalline and hydrated silicon dioxide. Opals have no definite shape, and can contain appreciable amounts of water. Water contents as high as thirty percent have been reported, although ten to fifteen percent is more the norm. Its specific gravity is quite low, ranging from 2 to 2.5. Sterling pendants with opal focal beads are quite common. These stones typically are quite light colored, and so they are sometimes paired with other more flashy gems such as rubies and sapphires. Mild colored specimens are generally less expensive than stones with bright and bold colors. Specimens with a bright luster are more desirable than dull ones. White opals are popular and quite common. At the other end of the spectrum, black opals are rare, sought after, and expensive.
Amethyst - A Beautiful Gem
Amethysts are a form of crystalline quartz. Amethyst crystals in nature can be quite large. The characteristic purple color of amethyst is a result of two secondary elements - manganese and iron. Manganese causes the stone to be purple in color. The iron content influences the intensity of the color. Darker colored stones are rarer are more expensive than lighter colored specimens. Recently however, the lighter colored Rose of France has become quite popular in jewelry designs. It is a February gemstone and is common in sterling pendants and other fine as well as costume jewelry. Amethysts are strong stones and as such, requite minimal care. These stones can be cleaned using an ultrasonic cleaner. Or, they can be cleaned using warm water, a gentle soap, and soft cloth. Prolonged exposure to heat and sunlight may alter the color of the stone.
Eye of the Tiger in Jewelry
Tiger eye is a relatively inexpensive gemstone that is used to make a wide variety of jewelry including sterling pendants, necklaces and bracelets. It has warm earthy colors that jewelry fans find quite endearing. Being a form of quartz, its properties are quite similar to those of quartz. It generally has a hardness of around 7 and a specific gravity of approximately 2.67. The stone contains iron oxide in the form of vertically oriented fibers that are luminescent. This property is called chatoyancy, and gives the stone the appearance of the feline eye. The stone is sometimes heat treated to change its color. Heat treated stones have a reddish color, and the change is irreversible. South Africa and Australia are the world’s largest producers of tiger eye. Some of these best quality specimens also come from these countries. Myanmar, Brazil, Canada, China, India, Namibia, and the United States of America are some of the other producers of this stone.
Agates in Jewelry - Common and Cheap - But Beautiful!
Agates are found all over the globe and are commonly used to make sterling pendants, brooches, other jewelry. Agates are a form of silica with crystals that are so tiny that they cannot be seen by the naked eye or even under moderate magnification. Impurities within the silica matrix give the stones interesting colors and patterns. They are found in many colors and patterns, with blues and greens being some of the less common colors. Agates from Botswana are famous for their very bright colors and intricate patters. While they are more expensive than other less colorful agates, Botswana agates are still relatively inexpensive when compared to other gemstones. The presence of iron oxide in silica gives the stone orange to brownish-orange colors. These specimens are called fire agates and are commonly found in South America and Mexico.
The Beauty of Aquamarine
Aquamarine is often incorporated into designs for sterling pendants, bracelets, and other jewelry. It has a light color and is almost transparent. Its neutral color compliments all skin colors, making it a popular gemstone. Although the name might suggest an association with sea or water, it is important to note that this association is only limited to the color of the stone, not its origin. Nonetheless, there are countless maritime legends associated with this gemstone. It is also called the gemstone of mermaids. Aquamarine is a March birthstone and is said to be lucky for Scorpios and Geminis. Stones with a darker and deeper blue are more expensive than light colored stones. Lighter colored stones are sometimes heat treated to improve their color. Larger stones tend to hold their color better and are usually deeper in color than smaller stones. Specimens with flaws or inclusions in them are less desirable than flawless ones.
Coral - The Gift from the Seas
Coral is a form of calcium carbonate that is formed from the skeletal remains of small sea creatures called polyps. It is commonly used to make sterling pendants, necklaces and bracelets. Coral and pearl are quite unique in that they are both created by living creatures. Most other gems used in fashion jewelry are inorganic and found on or near the surface of the earth. Under the right conditions of sea water temperature, coral reefs can continue to grow for over thirty years. Most of the coral used for jewelry today is found in the Mediterranean Sea and from the Pacific Ocean off the coats of Japan and Taiwan. Black coral was once found off the coast of Mexico; but this resource is generally depleted significantly. Coral that is free from fractures, cavities, or other anomalies is considered to be the highest grade coral, and is quite rare and expensive. Coral is generally treated before it can be cut and polished. In some instances, it may be dyed to enhance its color.
Jade - The Revered Gemstone
For a few millennia now, jade has been revered by ancient civilizations of Asia. It has been used to make carvings, statues, and other ornaments. The use of jade in jewelry such as sterling pendants, necklaces and bracelets came much later. An examination of records suggests that jade was first mined over 5000 years ago. Because of its strength and hardness, it was initially used to make primitive tools and hunting equipment. Later, man recognized the beauty of the stone and began to use it for decorative carvings and other aesthetic applications. Gemologists today recognize both jadeite and nephrite as jade. Jadeite is less common and is found mainly in Asia. Nephrite is more common and can be found in Burma, China, South America, Central America, Russia, Central Europe, and Canada.
Jasper as a Gemstone
Jasper is a common opaque semi-precious gemstone that is used in the design of sterling pendants, necklaces, and other silver jewelry. Nature has provided jewelry buffs with many varieties of jasper. Dalmatian jasper resembles the skin of the breed of dogs of the same name. The yellow and red dots of poppy jasper resemble poppy flowers. Landscape jasper, which is only occasionally used in jewelry, has surface patterns that resemble beautiful scenic views. Leopard jasper has orange and tan spots that resemble the markings of a jungle cat. It is believed that jasper protects the wearer from physical and mental dangers. It wards off negative energy and helps victims of depression. It is believed to aid with stomach ailments and complications related to pregnancies. Fancy jasper in particular, has brightly colored patterns, and is believed to cheer people up and generally improve the mental health and well being of the wearer.
The Story of Lapis Lazuli
Lapis Lazuli lapis as it is sometimes known for short, is a popular semi-precious gemstone used to make sterling pendants and other pieces of fashion jewelry. Artifacts found during archaeological excavations in present day Iraq and Egypt
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