Ruby is an artificial gems that is particularly appreciated by jewelers for its physical properties and rare hues ranging from very light red to dark red.

Properties of the ruby

The black star ruby belongs to the same family as sapphire, namely corundum, formed of crystallized aluminum oxide. Their hardness is known, making them the stones of choice for jeweler. Indeed, on the Mohs scale, which measures the hardness of the stones and has 10 levels, the ruby has a hardness of 9.

Dark ruby is corundum. It is distinguished by its red color, due to the presence of chromium in its composition. Corundum having any other color (blue, purple, yellow, orange, green, black, etc.) then designates the sapphire.

Different colors in which Ruby exits

The color of the synthetic ruby vs real ruby varies from light red to brown red, depending on the presence of chromium or iron in its composition. The most beautiful shade of ruby is called "pigeon blood" for its intense red color slightly tinged with blue. When the ruby is extracted, its hue is often unevenly distributed and its dimensions are quite variable.

It is the skilful size of the stone, traditionally produced in the countries of origin, which then gives it a homogeneous color and a balanced proportion. Very rare copies display an intense red color. The natural hues vary, however, depending on the country of origin, the rubies of Tanzania will have orange hues while the gems from Burma will be intense red tinged with pink. Burmese rubies are considered to be the most beautiful in the world. It is then the action of heating at very high temperature which comes definitely confer an intense and deep shade red ruby. This action also has the effect of reducing the opacity of the stones.

Hardness of the ruby

The first remarkable physical feature of the created ruby is its incomparable hardness. It is located (the corundum family of which it is a part) just after the diamond on the Mohs scale. A quality that is making a stone very popular with jewelers, but also watchmakers. The latter use them (synthetic) for the manufacture of bearings that support the pivots of the axes of the steel train, because of its resistance to friction of the metal. London blue is also famous stone and as beautiful as ruby.

Chemical properties of the ruby stone

The unique chemical formula of the ruby is Al2 O3, and its refractive index is low.

Its high resistance allows it to be heated to 1600 degrees to intensify the color and brightness without altering its original shape. This practice is common and accepted in jeweler. This heat treatment should not be confused with other treatments (lead or beryllium) that modify the stone unnaturally and are not accepted by the major jewelers. However, if this is the case, the customer must be informed and the treatment will be mentioned on the certificate of the stone.