Until recently, spinel was an underappreciated gem with little consumer recognition. Increasing demand for ruby alternatives rekindled appreciation for spinel’s rich red colour and history. In ancient times, southeast Asia’s mines yielded exceptional large spinel crystals, which became the treasured property of kings and emperors, often passing through many hands as spoils of war.
Birthstones & AnniversariesSpinel was recently added as an August birthstone, sharing this month with peridot and sardonyx. It has long been mistaken for ruby by emperors and monarchs. Many of the famous “rubies” of history were actually spinels.
Spinel crystals are so perfect, in Burma they are said to be nat thwe or “polished by the spirits.”
The famous 14th century Black Prince’s Ruby in the British Imperial Crown is actually a red spinel.
Mineralogist Jean Baptiste Louis Rome de Lisle identifies spinel as a different mineral than ruby.
There are a number of processes used to alter the colour or apparent clarity, or to improve the durability of gems.Learn More
Some gemstones have synthetic counterparts that have essentially the same chemical, physical and optical properties, but are grown by man in a laboratory.Learn More
Any gem can be imitated – sometimes by man-made materials or by natural materials chosen by man to impersonate a particular gem.Learn More
Why We Love This Gemstone
Singly refractive and often very transparent, red spinel rivals ruby’s colour but it costs much less.
Red spinel is coloured by chromium, the same trace element that colours ruby and emerald.
Birth of Gemology
Distinguishing spinel from ruby gave birth to the science of gemology.
An assessment of the following characteristics determines spinel’s value.
The most valued spinel colours are bright red, cobalt blue, and vivid pink and orange. Pale lavender is more affordable
Spinel with no visible inclusions is preferred. The more prominent the inclusions, the less valuable the gem.
Spinel is most often cut in cushion and oval shapes. When properly proportioned it has excellent brilliance.
Fine-colour spinel is rare above five carats. Most fine-quality rough is cut to non-standard sizes to save weight.
Spinel Quality Factors: The Comprehensive Guide
Explore sources, gemmological research and the role of gems in history.
Some Gemmological Challenges in Identifying Black Opaque Gem MaterialsMary L. Johnson, Shane F, McClure and Dino G. DeGhionno , Dec 1, 1996 Read more in English
Flux-Grown Synthetic Red and Blue Spinels from RussiaSam Muhlmeister, John I. Koivula, Robert C. Kammerling, Christopher P. Smith and Emmanuel Fritsch and James E. Shigley , Jun 1, 1993 Read more in English