Gemstone Information

SAPPHIRE

The September birthstone, most commonly blue, but occurs in pink, yellow, pinkish orange, orange, yellow, purple, green and colorless. The blue color is what most people think of as sapphire and is by far the most common color. In very simple terms the most valuable color of sapphire is a velvety corn flower blue. In even more tangible terms the more bright blue the sapphire, the better it is. Of course the cut and impurities inside the sapphire will affect the value as well. Sapphire is a very durable gemstone and second only to diamond in hardness. The vast majority of sapphires are heated to brighten or alter the color to make them more desirable. The heat treatment is permanent and unless clearly stated you should assume all sapphires are heat treated. A non-heat treated sapphire will command a premium price. The most valuable sapphires are non-heat treated and come from the Kashmir region of India.

EMERALD

The birthstone for May. The color of Emerald ranges from a light green/ yellowish green to a vivid green/ slightly bluish green. The most valuable color is a deep very slightly bluish green. Most emeralds have a significant amount of impurities that usually can be seen with the unaided eye. The finest emeralds have virtually no impurities, but the presence of minor and even somewhat significant impurities does not make an emerald undesirable, just a little more affordable vs. the purist ones. Emerald is fairly hard but not real tough. What this means is emeralds can be broken or chipped fairly easily. They should be worn with care. Most emeralds will be treated with cedar wood oil to minimize the visibility of surface reaching blemishes. Care should be taken when cleaning emeralds as harsh cleaning may dissolve the oil or damage the emerald. The most prized emeralds usually come from Columbia.

RUBY

The birthstone for July. Ruby is red and if it crosses the threshold of red into pink it is now a pink sapphire. Ruby and sapphire are the same mineral (corundum) and the red variety is ruby. Ruby is very durable and second in hardness to diamond. The most valuable color of ruby is pigeon blood red, this is a dark vivid red. Ruby often has a slight hue of purple resulting in a lower value. Of course cut and impurities will also affect the value. Often ruby will have no impurities to the unaided eye, but usually some impurities under a microscope. The presence of an eye visible impurity is not cause for alarm as long as the overall effect is not significant to the beauty of the ruby. Most rubies are heated treated to improve or alter the color and all rubies should be assumed to be heat treated unless specifically stated otherwise. The most valuable rubies are pigeon blood red, non-heat treated and usually from Burma.

ALEXANDRITE

Alexandrite is the birthstone for June (along with pearl). This gem is rare and found in Brazil, Sri Lanka and Russia. The name alexandrite comes from the Russian Czar’s daughter Alexandra. Alexandrite is traditional thought of as a Russian gemstone found in the Ural Mountains. This unusual gem is a phenomenal color change gem, which appears emerald green in daylight and ruby red in incandescent (normal indoor light bulb) light. Only the finest alexandrite gems show the vivid color change described and as the gems show less distinct color change the value decreases. The finest alexandrites rival the finest emeralds and rubies in value. Alexandrite possesses excellent toughness and can be worn with minimal fear of being damaged.

PEARL

The birthstone for June (Alexandrtie is also a June birthstone). Natural pearls are virtually nonexistent today. Natural pearls are those that are found in oysters where man has not inserted a seed (nucleus) to start the formation of the pearl. The pearls available today are cultured pearls grown on pearl farms with the growth process started by man with the insertion of a nucleus in the oyster. Pearl colors can be white, silvery, grey, beige, golden, black, greenish, pink and variations of these colors. Often cultured pearls are bleached or dyed to improve the color. In America the most desired color is white, silvery white or slightly pinkish. Some other cultures prefer other colors. The most desirable cultured pearls will have a very high luster (shiny surface), have few blemishes (bumps on the surface), be nearly perfectly round and when jewelry has multiple pearls they should match almost perfectly. Departure from these ideal characteristics is no cause for alarm. Pearls that are less then perfect may be very beautiful and offer a lifetime of enjoyment and in accepting a few "flaws" you may get lovely pearls at a price you are comfortable with. Cultured pearl size is described in millimeter diameter and 3-20 mm is the typical size range. The common sources for cultured pearls are Japan (Saltwater, usually 3-9mm, usually light colors), South Seas (Saltwater, usually 8-20 mm, usually light colors), Tahiti (Saltwater, 8-20 mm, usually dark colors) and China (Freshwater, usually 3-8 mm, light colors). Pearls should be worn with care. They can scratch and can be damaged by perfumes and any acids including acidic perspiration.

OPAL

October's birthstone (along with rose zircon and pink tourmaline as a substitute for opal). Opal is commonly known as an opaque milky color gemstones with flashes of red, blue and green (called play of color). Opal also occurs in almost any color and can be transparent to translucent. The most valuable opals are black opals. These have a dark (vs. milky) body color with very strong flashes of color, the more reds the better. The next most valuable opal is a boulder opal, which is a thin layer of opal grown over the host rock resulting in almost any color with very strong flashes of other colors. In the more common white opals the most desirable is an opal with very strong play of color, red flashes being the most desired. Because opals have such a large variety of looks the best way to determine what to purchase is what appeals to you. Every opal is very unique and you may happen to love one that may not be even close to the most costly. Opals should be handled with care as they break easily and are sensitive to high temperatures. A hot light bulb can damage or destroy an opal. With reasonable care opals will offer a lifetime of enjoyment.

PERIDOT

Peridot is the August birthstone. The normal color range for peridot is a light yellowish green to a fairly dark slightly yellowish green color. Occasionally peridot will be found in a light brown color. This gemstone often has no impurities visible to the unaided eye but usually has some obvious impurities when viewed with magnification. The major source for peridot is the United States.

TOURMALINE

Tourmaline is a gemstone that occurs in almost every color, the pink variety is used for the October birthstone as a substitute for the much less available pink zircon. This gemstone usually has some eye visible impurities, although if not excessive these are not a cause for concern. Tourmaline is a gemstone that should be worn with care as it only exhibits fair toughness. Because tourmaline is often found in long crystals and is often cut as a very long stone it is often seen in one of a kind custom jewelry. Major sources of tourmaline are Brazil and Afghanistan.

TOPAZ

Topaz is the November birthstone (golden color) and it occurs in most colors. The smoky darker blue topaz (called London blue) is used as the December birthstone as a substitute for the less common blue zircon. The most valuable topaz is an orangey pinky peach color called precious topaz or imperial topaz. Topaz is normally pure to the unaided eye and often pure even when viewed with magnification. Some topaz is heat treated to achieve more pinkish/red colors. Most blue topaz has been irradiated to get the blue color. The blue variety is not radioactive except in very rare cases. Topaz can be worn regularly but a sharp blow can damage this stone more easily than most gems because topaz has strong cleavage. Major sources for topaz are Brazil and Nigeria.

CITRENE

Citrene is a yellowish gemstone that is used as the November birthstone as a substitute for the more costly golden topaz. Citrene is often confused with and even called topaz. This gemstone is usually free of impurities and because it is reasonably available it is reasonable in price. Citrene has good toughness and can be worn without significant worry. Citrene may be heat treated to achieve the desired color and this treatment is undetectable. Citrene is usually free of impurities. The major source for citrene is Brazil.

BLUE ZIRCON

Blue zircon is the December birthstone (tanzanite, turquoise and blue topaz December). This is a fairly uncommon gem that most people have never seen. Zircon (not to be confused with cubic zirconium) is a highly refractive and dispersive gem which means it has very good sparkle and shows a lot of reflected colors. Blue zircon has usually been heat treated. This gem is not a tough one and should be worn with care. Zircon is often free of visible impurities. Major sources for zircon are Kampuchea, Sri Lanka and Burma.

BLUE TOPAZ

Blue topaz is used as a substitute birthstone for December (see blue zircon). Blue topaz occurs in light blue (sky blue), Medium bight vivid blue (Swiss blue) and in darker grayish smoky blue (London blue). See topaz for other characteristics.

TANZANITE

Tanzanite has recently been designated as an additional birthstone for December. Tanzanite occurs in all shades of blue to purple, a vivid deep blue with hints of purple is considered the most desirable. This gem is normally free of impurities. Most tanzanite has been heat treated. This gem is not real tough and should be worn with care. The source for tanzanite is Tanzania.