The fresh lime green of peridot is its distinctive signature, and the gem is one of few that occur in only one color, a rich yellow-green. Peridot’s apple-green hue has been treasured for over 4,000 years. The Ancient Egyptians revered it as the “gem of the sun”. The location of Egypt’s fog-shrouded volcanic mines on the Red Sea island of Zabargad were a closely guarded secret, and stones they dug from there are the source for many large fine peridots currently in the world’s museums. The Romans dubbed it “evening’s emerald” because unlike the deep-green emerald, Peridot’s citrus tones remain constant even by candlelight. In the Middle Ages, Europeans adorned cathedrals with fine peridot stones.
Although Hawaii’s volcanoes have produced some peridot large enough to be cut into gemstones, virtually all peridot sold in Hawaii today is from Arizona, another state with extreme geology. Most of it is mined, often by hand, by Native Americans on the San Carlos Apache (Nde) Reservation in Arizona. Peridot found here is beautiful in color but relatively small in size. Faceted peridot from Arizona is rare in sizes above five carats.
In 1994, an exciting new deposit of fine peridot was discovered in Pakistan, 15,000 feet above sea level in the far west of the Himalaya Mountains in the Pakistanianpart of Kashmir. The gemstone can be found in North America in Arizona, Arkansas, Hawaii, Nevada, New Mexico and Mexico. Other sources include areas in Australia, Brazil, China, Egypt, Kenya, Myanmar (Burma), Norway, Kashmir, Saudi Arabia, South Africa, Sri Lanka, and Tanzania.
Peridot is also one of the few gemstones to be found to come from outer space. Found in pallasite meteorites, extraterrestrial peridot is one of the rarest gem materials on Earth. In 2005, peridot was found in comet dust brought back from the Stardust robotic space probe.
Peridot is harder than metal but softer than many gemstones. Store peridot jewelry with care to avoid scratches and protect from blows. Because peridot is sensitive to rapid changes in temperature, never have it steam cleaned and avoid ultrasonics. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.
Spinel’s name comes from Latin “spina”, meaning “arrow”. You may also find spinel in black, violet blue, greenish blue, grayish, pale pink, mauve, yellow or brown. Vivid red is the most desirable color of spinel gemstones, followed by cobalt blue, bright pink and bright orange. The more affordable stones are often those with paler colors, like lavender.There is a unique natural white spinel, now lost, that surfaced briefly in what is now Sri Lanka. With a hardness of 8 on the Moh’s scale, spinel is a durable gemstone suited for any type of jewelry.
In ancient Sanskrit writings, the gemstone spinel was called the “daughter of ruby”, and for centuries, red spinels were called spinel-rubies or balas rubies. “Balas” is derived from Balascia, the ancient name for Badakhshan, a region in central Asia. Mines in the Gorno Badakhshan region of Tajikistan were the main source for red and pink spinels for centuries.
It wasn’t until 1783 that spinels were differentiated from rubies. The two gemstones can be distinguished on the basis of their chemical properties: a red spinel is a compound of magnesia, iron, oxygen, and chromium, while a ruby is a type of aluminium oxide. After the 18th century the word ruby was only used for the red gem variety of the mineral corundum and the word spinel came to be used.
Examples of famous rubies that are actually spinel include pieces in the British Crown Jewels. One is called the “Black Prince’s Ruby,” which is actually a 170-carat red spinel. Similarly, The Timur Ruby, a 352-carat gemstone once owned by Mogul emperors and now held by Queen Elizabeth, was also recently discovered to be a red spinel. Part of the reason behind the misidentification of these gemstones is that spinel is often found in the same gemstone bearing gravels as ruby and sapphire. Distinguishing features, like its octahedral crystal structure and single refraction, are what sets it apart from other gems. Spinel also has a lower Mohs hardness than ruby and sapphire.
Spinel has long been found in the gemstone-bearing gravel of Sri Lanka and in limestones of the Badakshan Province in modern-day Afghanistan and Tajikistan; and of Mogok in Burma. Recently gem quality spinels also found in the marbles of Luc Yen (Vietnam), Mahenge and Matombo (Tanzania), Tsavo (Kenya) and in the gravels of Tunduru (Tanzania) and Ilakaka (Madagascar).
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