Rubies and sapphires are composed of almost pure aluminum and oxygen and are members of the corundum family. The mineral is often called a ruby when it is red and a sapphire when it is blue. The ruby and sapphire needs to be transparent or nearly so to be considered gem quality. Few are found this way in the natural state. Rubys and sapphires that are unfit for gem use, like diamonds, are also used for mechanical purposes because of their hardness. Both gems have a hardness of 9, and a specific gravity of 3.9 to 4.1, only diamonds being harder. The best non gem quality stones are used for bearings in fine machinery. They are also used as jewels for watches and certain electrical supplies.



The color of rubies comes from a small quantity of oxide of chromium. The color in rubies as well as sapphires are rarely even throughout. Often this defect can be remedied with the proper application of heat. One of the greatest characteristics of rubies is that they are just as brilliant in natural light as they are in artificial light. Large flaw less, and transparent rubies are extremely rare and often times in large sizes they are more valuable than diamonds. The largest ruby in the world is the Raviratna, and it weighs 3,600 carats. Both gems were considered protection against poisoning in earlier times.

Rubies and Sapphires are found in Burmah, Siam, Ceylon, Afghanistan, Thibet, Australia, North Carolina, and the United States. The finest rubies are found in Burmah. The Rubies mined in Upper Burmah have been mined since the fifteenth century. Rubies are usually found in mines, hill sides, clay, valleys, and rivers. Rubies color depends often upon which part of the world that they came from. Rubies come in all shades of red, black, blue, and purple. Too much heat can destroy a rubies color entirely but just enough can enhance color. It is very difficult to tell if these gems have been heat treated.

The emerald is a green beryl. A perfect emerald is rarer than any other stone. Some believe that the emerald gets its color from small quantities of organic matter in them. Most scientists believe that the color is due to an oxide of chromium. The emerald is subject to many structural defects, flaws, muddiness, and variations of color. Usually, the better the color, the more faulty it is. A flawless mineral of very fine color is almost unknown. The emerald is made up of silica, an oxide of silica. The rest of the mineral is made up of equal shares of alumina and glucina.

Emeralds have been discovered in a few places scattered around the world. Emeralds were first discovered in great quantity in Peru. Many of Perus emeralds, along with a lot of its precious metals were stolen by Spanish marauders. It is believed that one ship of marauders returned to Spain in 1587, with two chests, each of which had one hundred weight of emeralds. Emeralds have also been discovered in Africa, Egypt, Columbia, Austria, and some have even been found in North Carolina and Connecticut.

The Emerald is considered to bring good luck and well being. One of the largest in the world is the Mogul Emerald which dates back to 1695 and weighs 217.80 carats.

Description

Rubies and sapphires are composed of almost pure aluminum and oxygen and are members of the corundum family. The mineral is often called a ruby when it is red and a sapphire when it is blue.