There are hundreds of different gemstones that are set into settings of silver, gold or platinum to make nearly infinite combinations of jewelry that can be used to enhance beauty and appearance. Here is information on a small sampling of the most popular gemstones available.
This is the birthstone for March and is a member of the beryl family. Aquamarines range in color from almost colorless blue to blue-green or teal. Deep blue aquamarines are the most valuable. Aquamarines are a 7.5 on Mohs hardness scale.
A pure beryl stone is colorless but it also comes in other colors including yellow, green, blue, red or even pink. Red beryl stones are the most rare. Beryl is most valuable when the stone is a dark, vibrant color. They rate as a 7.5 on the Mohs hardness scale and can be mined in California, Pakistan, Russia, Brazil, Africa and Columbia.
The hardest natural substance known to man is the diamond. Known for its shining, sparkling radiance, its ability to take many cuts and reflect brilliance as a result, diamonds are the most expensive stones on the market Rated a 10 on the Mohs hardness scale, diamonds also have uses in industry as a polish (diamond dust) and for cutting other hard substances. Diamonds can be black, blue, yellow or any level of variation therein, with a clear, perfectly colorless diamond having the most value.
Another member of the beryl family, emeralds are only emeralds if the beryl is green in color, while the most valuable stones have a deep, “grass green” color. Mined in many countries, including the U.S., the most valuable emeralds come from Columbia. Usually emeralds have many cracks in them, and a process of oiling them to fill in those cracks is a common and perfectly acceptable practice. Even though they have a 7.5 on Mohs hardness scale like other beryls, emeralds tend to be brittle stones and should never be steam cleaned or given an ultrasonic bath.
Are the official birthstone for January, and they may also be used as a present for the 6th wedding anniversary. Garnets can be mined in any color except blue, and the specific garnets are named for their colors, for example Rhodolite is a reddish color while Tsavorite is the name given to dark green garnets. Garnets are a 7 on Mohs hardness scale and are mined in many places around the world.
Jade is a name given to various forms of jadeite and nephrite, though jadeite is quickly taking its place as the only “true” jade stones and are the most valuable. Imperial jade, which only comes from Myanmar, is an emerald green in color and is considered the most valuable of all. Some jades can be white, yellow, pink, black or purple and come in virtually any shade or hue of green. Jade rates a 6.5 on the Mohs hardness scale.
Onyx is the birthstone for the month of December and is the name given to a type of chalcedony quartz stone that is usually mined in California, India, Brazil and Uruguay. Usually onyx is pure black, but may be streaked with browns and white. Onyx is a beautiful stone when its black is shined and polished to a fine, high luster, and it is often used as a carving stone.
Opal is the official birthstone for October. This stone is mined in various types all around the world and is often a bluish in color, but may also be white or brown, or any combination. With a 5.5 on the Mohs hardness scale, opals are still very durable stones and they crack only very rarely due to their extremely low water content.
June’s birthstone is the pearl and are the only organic gemstone. Pearls are formed inside mollusks like oysters and mussels. It takes up to eight years to form a decent-sized pearl, and the most valuable ones are symmetrical and not produced under farming conditions. The iridescent quality of pearls is what gives them their beauty and makes them desirable. Pearls may contain many colors other than the traditional cream/white including black and pink or brown. Due to their organic nature, pearls are fairly soft, having only a 2.5 – 4.5 rating on the Moh’s hardness scale. They should be treated with extreme care and kept away from harsh chemicals at all times.
Red corundum stones are known as rubies. Though corundum can come in many colors, only the red ones are known as ruby stones. Rubies are extremely hard, second only to diamonds and receive a 9 rating on the Mohs hardness scale. Rubies may be pale red and almost pink in color, though the most valuable rubies are a deep red. Ruby is a classic example of stone where the color of the stone is the primary consideration in its value, even above the carat (size) of it.
Also a corundum, sapphires are just as hard as rubies (9 on the Mohs hardness scale), and are the other-than-red variety of this precious stone. The most popular color for a sapphire is blue, but they can be just about any color imaginable. These stones have an amazing ability, when they receive a cabochon cut to exhibit a “star” of light in their interior. Six ray stars are the most common but there are twelve ray stars as well. Another effect from this cut may also produce a cat’s eye effect. Sapphires may be artificially for lower – priced jewelry, and is nearly indistinguishable from the natural stones.
What are the different types of gemstone cuts?
Not all stones can receive the same types of cuts due to their chemical composition and softness. Also, due to the way the stones reflect the light, their beauty may be seriously impacted by certain cuts. Pearls, for example, are never cut, and opals are very limited in the types of cuts they can receive in order to keep them from breaking. Diamonds may receive many cuts and are open to any of the types listed below:
- Round Cut: The traditional and most popular diamond shape – think Superman.
- Pear Cut: Also known as a teardrop. Has 58 facets.
- Oval Cut: Are oval in shape when viewed from the top. Has 56 facets.
- Marquise Cut: Are longer ovals with “pointed” ends. Has 56 facets.
- Emerald Cut: The traditional, rectangular shape for emeralds.
- Princess Cut:A square cut with sharp, uncut corners. Has 76 facets.
- Heart Cut: Increasingly popular, these diamonds have the traditional heart shape and are used for romantic occasions.
- Radiant Cut: Radiant cuts are square like the princess, but the corners are slightly rounded. Has 62-70 facets.
- Triangle Cut: Triangle cut diamonds are rare in jewelry and typically only used for very large stones.
What are the Four Cs in rating gemstones?
Clarity, Cut, Carat and Color. The value of each will vary from gemstone to gemstone, but usually the color of a stone is the most important aspect in determining its value.
- Color: The color/hue of a stone. Unless you are dealing with stones that are traditionally clear such as diamonds, generally a stone with a dark, deep hue is more valuable than a pale one.
- Clarity: How clearly a stone catches or reflects light. Some stones such as onyx, are black and clarity in them is a measure of how clear of imperfections the stone is on the surface.
- Cut: How a stone is cut. Not important for all stones (pearls, for example, are never cut), the shape and quality of a stone’s cut does much for its value.
- Carat: The size of the stone. Though this is often the first thing people look for when choosing a stone (the most carat they can afford), it is not the factor that gives most stones their greatest value.