Sapphire Definition - Taken from Encyclopedia Brittanica
Transparent to translucent natural or synthetic variety of corundum that is highly prized as a gemstone.

Its color is due mainly to the presence of small amounts of iron and titanium and normally ranges from very pale blue to deep indigo. Colorless, gray, yellow, pale pink, orange, green, violet, and brown varieties also are known as sapphire; red varieties are called ruby. Synthetic sapphire has been produced commercially since1902. Much is used in jewelry, but most is used in the manufacture of jewel bearings, gauges, dies, and other specialized components; some also is used as a high-grade abrasive. It is found in Sri Lanka, Myanmar, and India and occurs in Montana in the U.S.

 

Corundum - Definition - Taken from Encyclopedia Brittanica
Aluminum oxide mineral (Al2O3) that is, after diamond, the hardest known natural substance.

Gem varieties are sapphire and ruby; mixtures with iron oxides and other minerals are called emery. Corundum is widespread in nature, although large deposits are rare. Rich deposits occur in India, Russia, Zimbabwe, and South Africa. In addition to being a precious gem, corundum is used as an abrasive for grinding optical glassand for polishing metals and has also been made into sandpapers and grinding wheels. For most industrial applications, however, it has been replaced by synthetic materials such as alumina; synthetic corundum is also manufactured.

When we think of sapphires, we think of blue. However, in Montana, and other parts of the world, sapphires come in all colors. Their mineral name is corundum. A ruby is the same mineral, but red. The four precious gems are considered to be Diamond, Sapphire, Ruby and Emerald, so when you have a sapphire, you indeed have a very precious treasure. It is believed that sapphires are four times more rare than diamonds.

The different colors of sapphires are caused by trace mineral impurities within the corundum. Another impurity causes a cloudiness that interferes with the brilliance of the sapphire when cut into a gem. In order to improve the clarity of the stone, before cutting, the sapphire is heated to high temperatures, which removes the cloudiness and at the same time usually intensifies the color. We can make calculated guesses as to how the stone will respond to the heat-treating, but mother nature has her own ideas, and we sometimes are surprised. We are seldom disappointed, however. Occasionally we will recommend leaving a stone in it's natural color state if it is especially clear, and if it has a unique color.

The average Montana Rock Creek sapphire color in it's natural state is a mint blue/green color, smaller than the size of a pea. After heat-treatment, the stone usually becomes a more intense richer blue color. In general, the more cloudiness the stone exhibits in it's natural state, the more intense the blue after heating. It is very difficult to get two perfectly matched stones, but most people are very happy with the variety of the Montana sapphires.

Sapphires are very durable, just under diamond in hardness. Therefore they are the perfect choice for jewelry that is meant to be worn. The different colors of sapphires and their extraordinary brilliance make them very personal stones. Like people, no two are alike, and when selecting a stone, you will find that you are drawn to different colors or tones than you might expect, especially if you are new to the idea that sapphires are not just blue ! The other colors are referred to as " fancies " or " party colors " and our deposit is unique in that we occasionally find stones that are more than one color within a stone, sometimes referred to as " pintos". Fancy colors are much more rare than the blues, and often command a higher price per carat.

The sapphire is the birthstone for September, usually thought of as blue, although as the public becomes aware of the different colors, people are choosing their own preferred color for their jewelry these days. The sapphire is also the anniversary stone for the 45th wedding anniversary, and it is indeed a precious stone to use for a special celebration. In addition to the traditional uses, many are now choosing various colors of sapphire for representation of birth months in family jewelry, as mother's rings and pendants. It is often possible to find sapphire colors similar to the colors of the different months birthstones, giving a richness of color and better durability to the piece. Another very popular way of adding sapphires to your jewelry is to incorporate them into heirloom jewelry. Many family rings can be given new life by adding sapphires, or by replacing lost or removed stones with sapphires. Especially beautiful are diamonds rings that have been enhanced by the incorporation of brilliant colorful sapphires, a stunning combination.

 

More Sapphire information on our Heating, Treating and Cutting page.