Rubies and sapphires belong to the corundum of the mineral family. However, only the red form of the mineral is called ruby. The red color of rubies is mainly caused by the presence of the chromium element. The name ruby ​​derives from ruber, Latin for red.

Rubies belong to a class of their own and rank among the rarest gemstones in the world.

Large natural rubies (5 or more carats) often cost more on a per carat basis than white diamonds. Montepuez's ruby ​​deposit at Gemfield in Mozambique is believed to be the largest in the world and has produced some phenomenal (uncut) rubies, including the 40-carat "Rhino Ruby" and a matching 45-carat pair of "eyes. of the dragon.

Montepuez Mozambican rubies often show a low iron content. This is a good feature and makes rubies more desirable, as too much iron can darken the rubies and dull the fluorescence. Burmese rubies from the Mogok area regularly have a vibrant red hue due to their specific formation within the marble.

Montepuez rubies have also been certified by leading independent laboratories as "pigeon blood" in color, making them one of the most sought after rubies in the world.

Rubies that are dull, have a weaker color or contain impurities can be enhanced with heat treatment. There is nothing wrong with this practice, as long as the treatment is fully disclosed to the client. The heating process, which typically takes place at over 1000 degrees Celsius, improves color and apparent clarity.

Natural unheated rubies are the most desired of these gemstones and demand the highest prices. Mozambican and Burmese rubies have the same beauty and one is no more sad than the other. It is important to point out. Gemfields Mozambican rubies are likely mined, they are also sold to the jewelry trade in raw form through transparent auctions, ensuring that Mozambique and its people receive the full tax benefit.