Organic gemstones aren't really gemstones. They constitute a special category within the world of precious stones. While most other gemstones, such as sapphires, diamonds, and amethysts, are made of minerals and have a crystal structure, organic gemstones come from living matter, such as plants and animals.
Organic gemstones are a small group, with the most well-known in this category being pearls , amber, coral, jet, and shells . They have been used since ancient times for the manufacture of jewelry and ornaments.
Pearls and mother-of-pearl
Mother-of-pearl necklace by 9Avril
Pearls and mother-of-pearl usually come from oysters, but they are also found in clams and mussels. A pearl forms when an irritant, such as a piece of shell or fish scales, is found in the shellfish. Over time, the animal covers this irritant with successive layers of nacre, until it transforms into a pearl.
Pearls come in a variety of shapes, although in nature the perfectly round shape is rare and therefore has always been more sought after. They also come in a range of colors, such as white, cream, gold and black.
Unlike other organic gemstones, pearls are grown and harvested. The only difference here is that the pearl farmer carefully inserts the irritant into the oyster and then lets the oyster do its job. This type of pearl is called cultured pearl.
Although pearls make beautiful jewelry , they are very soft (2.5 to 4 on the Mohs scale) and can easily be damaged. Pearls always come back into fashion and are currently very trendy and in high demand.
Amber
From the living world of oysters, we now move on to plant sap. Amber is the fossilized resin of pine trees, dating back over 50 million years. This glowing, hardened substance was one of the first to be used to create ornaments and has been made into jewelry since ancient times.
One of the most distinctive characteristics of amber is the intrigue of natural inclusions it typically contains. Small insects and pieces of plants are often found preserved in amber. Amber containing such inclusions is often more expensive and sought after, as it adds depth and character to the piece.
Amber comes in a range of warm, golden tones, from pale yellow to darker browns. Real amber has a subtle pine scent and is warm to the touch. It has a waxy, plastic feel and is very soft, rated 2 to 2.5 on the Mohs scale.
The coral
Coral is found in the ocean and is made up of tiny sea creatures, called coral polyps. Coral reefs are made of calcium carbonate, which polyps secrete to build their protective, hard home. Over time, coral reefs grow as the polyps die in their home and become part of the structure. Each subsequent generation of polyps builds its house on top of that of the previous generation.
Corals used in jewelry are often translucent or opaque and come in a range of vibrant hues, the most popular being red, orange, pink, white and purple. Coral is often made into cabochons, beads or cameos. For a natural, tropical look, jewelers try to retain the natural shape of coral when creating their designs.
In its natural state, coral is not lustrous, but when polished and waxed, it exhibits a smooth, lustrous sheen. It is rated 3-4 on the Mohs scale.
Shells
The shell has been used throughout the world since ancient times. It is the oldest form of jewelry, dating back approximately 100,000 years. Some varieties of shells were even used as currency in some cultures, such as Papua New Guinea, and the practice still exists today.
The shell is very easy to work with, as it is soft and easy to carve, but also very strong and durable. With proper care, shell jewelry can last a lifetime.
Under the term seashell are a number of different varieties, including mother-of-pearl, abalone, conch and ammonite.
The shell was used to create cameos, beads, cabochons, sculptures and figurines. Even today, shell is a commonly used material in jewelry making.
Organic stones are a special group of gemstones and have a long and remarkable history. They are among the first precious stones used in jewelry. Although some have fallen out of fashion for various reasons, organic stones have been indispensable members of the jewelry world. Every piece of organic gemstone has a story and is full of character and, even today, some are as popular and coveted as ever.