imperial state crown of the United Kingdom - spinelimperial state crown of the United Kingdom - spinel

Four Famous Spinels


Although the world’s most famous spinels are named “rubies,” these gems are distinct species. Learn the stories behind four of these jewels.

7 Minute Read

famous spinels  - The Black Prince Ruby
The large, red cabochon at the front of the Imperial State Crown of the United Kingdom is the famous Black Prince’s Ruby. Despite the name, it’s one of the most famous spinels in the world. Source: G. Younghusband; C. Davenport (1919). The Crown Jewels of England. London: Cassell & Co. p. 6. Photo is Public Domain.

The Black Prince’s Ruby

Most likely mined in Afghanistan, the spectacular 170-carat red stone that would become known as the Black Prince’s Ruby was what was known as a balas ruby. For centuries, people in Europe, the Middle East, and Asia classified these gems as a type of ruby but with some differences in properties and value. The French mineralogist Jean-Baptiste L. Romé de l’Isle scientifically distinguished spinels and rubies (corundum) as distinct mineral species in 1783. Since then, many “balas rubies” have been identified as spinels, including the Black Prince’s Ruby.

medieval tableau featuring balas rubies
This tableau of the Trinity from the early 15th century, made in England or France, features pearls, sapphires, and spinels, which at the time were identified as balas rubies. On display at the Louvre, Paris. Photo by Vassil. Public Domain.

A Fatal Attraction

The first recorded


International Gem Society


Emily Frontiere

Emily Frontiere is a GIA Graduate Gemologist. She is particularly experienced working with estate/antique jewelry.

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