 
The birthstones for December are the zircon and turquoise.Zircon probably gets its name from the Arabic zar (gold) and gun (color). This gemstone is found in igneous rocks and comes in a variety of colors. During the Middle Ages, zircon was worn by travelers as an amulet for protection from sickness, injury, and insomnia. Mohs hardness: 6.5 to 7 Refractive Index: 1.96-2.01 Specific Gravity: 4.65-4.8 The toughness of zircon is fair. They may be cleaned with steam, ultrasonic, jewelry cleaner, soap, or an untreated cloth. Turquoise is a soft opaque gemstone that takes a good polish and is admired for its beautiful sky blue color. The blue color is due to the presence of copper. Iron often provides some greener tones. Turquoise sometimes has a rock matrix and varying shades of grey, brown, or black veining due to inclusions or oxide stains. Turquoise is one of the first gems ever used for jewelry. The name of the gem is apparently related to the fact that it was brought to Europe from the Eastern Mediterranean by Levantine traders, generally known as Turks. It has served as an ornament for a very long time, having been used by the Egyptians for some thousands of years BC. Turquoise jewelry was found with a 7,500 year old Egyptian mummy. Turquoise beads from Mesopotamia (Iraq) date back to 5000 B.C. Turquoise mining in the Americas started about 1000 years ago. The ancient Aztecs mined it in what is now known as New Mexico. This treasured gemstone has been discovered in burial sites from Argentina to the Southwestern United States. It is one of the most controversial gems because much of the material sold has undergone so many different treatments that its original appearance has been completely transformed. Turquoise is found in Iran, United States (Nevada, Arizona, California, and New Mexico), and the Sinai Peninsula. Mohs hardness: 5-6 Refractive Index: 1.61 Specific Gravity: 2.7 The toughness of turquoise is good; however, it may be cleaned only with pure, mild soap or an untreated cloth.
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