A group of transparent stones of different colors, including peony-red, cherry-red, yellow, green and blue.
The most sought-after shade is cherry-red, whose resemblance to the ruby is such that it was often mistaken for the red corundum until the mid-nineteenth century.
The French even named it the “balas” ruby, after Balash in Afghanistan where such spinels were reputedly mined.
Poet Olivier de Magny (1529-1561) wrote these lines for his beloved, Louise Labé: "the two balas rubies of your tempting lips, and the sparkle of your eyes that slowly enchants me."
Most legendary “rubies” are in fact spinels: the Black Prince’s Ruby, part of the British crown jewels and weighing 170 carats; another weighing 414.30 carats that was set in the crown of Empress Catherine II of Russia and can now be seen in the armories museum in Moscow; and the 105-carat “Côte de Bretagne”, sculpted to resemble a dragon which was part of Duchess Anne of Brittany’s dowry.It can now be seen at the Louvre Museum in Paris.
Magnesium aluminate. Hardness: 8. Its planet is Saturn. Madagascar, Sri Lanka, Pakistan, Thailand, Afghanistan.