Blue Sapphire is one of the world’s most popular gemstones, ranging in color from light cornflower to deep, velvety navy and midnight blue. Second only to diamond in hardness, Sapphire is durable and well suited for everyday wear, including engagement rings. Sapphire is the birthstone for September. Fancy Colored Sapphire is the term used to describe shades of corrundum that fall outside the Ruby and blue Sapphire categories. Providing an array of choices for customers with a passion for color, Fancy Colored Sapphires are found in a spectrum of hues from vivid pinks to yellows, purples, greens and orange. Sapphire is often treated through use of controlled heating to permanently enhance color and clarity.
Ruby is the red variant of the mineral corundum, sharing the same physical properties as Sapphire. Ruby is mined throughout South East Asia with Thailand and Myanmar (Burma) producing some of the best qualities and colors. Ruby is the birthstone for July as well as the gemstone for fifteenth and fortieth anniversaries. Rubies are generally heat treated to improve color and clarity.
Emerald is the green gem variety of the minerl beryl, and is mined predominantly in Colombia, Zambia, Brazil, Zimbabwe and Pakistan. In selecting an Emerald, color is the most important factor, and most Emeralds, even of the highest quality, will contain tiny fissures and flaws which do not detract from the value of the stone. Emerald is the birthstone for May and is rated fair to good for everyday wear. Extremes of temperature and aggressive forms of cleaning may damage the stone.
Tanzanite is a relatively new addition to the gemstone family. Discovered in 1967 and a variety of the zoisite mineral category, Tanzanite is found in only one place in the world, in the Mount Kiliminjaro region of Tanzania, East Africa. Tanzanite ranges in hue from shimmering lilacs and light blues to radiant deep blue-violets and indigos. In 2002, the American Gem Trade Association added to its list of birthstones, unchanged since 1912, naming Tanzanite a birthstone for the month of December. Tanzanite is routinely enhanced through heating at relatively low temperatures.
Tsavorite was first discovered in 1967 in Tanzania’s Tsavo National Park. Now also mined in Kenya, Tsavorite is popular for its striking green tones, which range in a spectrum from light grassy green to deep, dark forest green. Tsavorite’s brilliance and luminosity is evident even in small sizes, while cut and polished stones over two carats in weight are extremely rare. Tsavorite is rated good for everyday wear.
First discovered in Russia, Alexandrite is known for its ability to change color in different lights. In daylight, Alexandrite is a medium greenish-blue, but in incandescent light, it glows a rich pink or purplish red. Today, sources of Alexandrite include Brazil, Tanzania, India, Madagascar and Burma. However, top quality Russian Alexandrite showing its two colors distinctly is more rare than ruby, Sapphire or Emerald.
For further information on colored gemstone properties and care, please refer to The Gemstone Information Manual published by AGTA, or visit http://www.agta.org