{"id":35597,"date":"2026-06-14T08:30:00","date_gmt":"2026-06-14T08:30:00","guid":{"rendered":"https:\/\/ckystones.com\/?p=35597"},"modified":"2026-10-05T03:09:39","modified_gmt":"2026-10-05T03:09:39","slug":"le-spinelle-une-gemme-aux-mille-reflets","status":"publish","type":"post","link":"https:\/\/ckystones.com\/en\/le-spinelle-une-gemme-aux-mille-reflets\/","title":{"rendered":"Spinel \u2013 A magnificent gem with a thousand reflections"},"content":{"rendered":"
\"Spinelle
Set<\/figcaption><\/figure>\n\n\n\n

Among the most captivating gems, yet long overlooked, spinel occupies a distinctive place. Far less well known than ruby or sapphire, it nevertheless appeals to enthusiasts and collectors through its beauty, rarity and rich palette of colours. Now rediscovered by high jewellery, spinel is establishing itself as an important gem in its own right, combining history, brilliance and authenticity.<\/p>\n\n\n\n

The word spinel<\/a> comes from the Latin spina, meaning \u2018thorn\u2019 or \u2018point\u2019, a direct reference to the octahedral shape of its crystals, which resemble small pointed forms, or from the Greek \u2018spinther\u2019, meaning sparkling or glittering. Its etymology remains debated, although the Latin origin is the most widely accepted.<\/p>\n\n\n\n

It is a mineral belonging to the family of magnesium aluminium oxides, with the formula MgAl2O4, and is often found as well-formed crystals. Its chemical composition and crystal structure make it a durable stone sought after in jewellery. Long confused with other gems, particularly ruby, spinel was sometimes called \u2018balas ruby\u2019, an old term for red stones extracted from the mines of Balascia or Badakhshan.<\/p>\n\n\n\n

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Characteristics and colour palette<\/strong><\/h2>\n\n\n\n

Spinel is a mineral with a vitreous lustre and a hardness of 8 on the Mohs scale, making it suitable for everyday jewellery. One of its most distinctive features is its diversity of colour. Intense, fiery red spinel is undoubtedly the most sought after and is sometimes confused with ruby. However, the stone also comes in blue, pink, violet, orange, black and even colourless forms. Among the rarest and most prized are saturated blue spinels, often from Vietnam or Sri Lanka, and vivid reds or pinks from Burma. This variety of colours is explained by impurities such as chromium, iron or cobalt.<\/p>\n\n\n\n

Spinel is known as a gem that is almost always natural and untreated, one of its major advantages compared with rubies and sapphires. However, there are a few documented exceptions:<\/p>\n\n\n\n

\u2013 Nickel diffusion, GIA \u2013 14\/02\/2023: blue-green colour induced by nickel diffusion, with artificial healing of fractures. \u2018GIA Researchers Identify New Spinel Treatment \u2013 GIA \u2013 14\/02\/2023\u2019<\/p>\n\n\n\n

\u2013 Cobalt diffusion, SSEF \u2013 June 2018: a dark blue variety obtained by surface diffusion of cobalt. \u2018Cobalt diffusion-treated spinel, 01\/06\/2018, SSEF\u2019<\/p>\n\n\n\n

\u2013 Heating, GIA, autumn 2021: low-temperature heating (600\u20131000 \u00b0C) is possible and alters colour or clarity; PL\/Raman spectroscopy enables detection. \u2018GIA Gems & Gemology, Fall 2021\u2019<\/p>\n\n\n\n

\u2013 Fracture filling, IGS \u2013 10\/06\/2023: fractures are uncommon but may be stabilised by filling them with oil or resin to improve transparency. \u2018Spinel Treatments and Enhancements \u2013 International Gem Society \u2013 10\/06\/2023\u2019<\/p>\n\n\n\n

Synthetic spinel also exists, produced mainly by the Verneuil or flux methods since the early 20th century. These synthetic spinels can reproduce the colours and brilliance of natural stones and are mainly used in mass-market jewellery and industry.<\/p>\n\n\n\n

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CC Koreller, rough Verneuil synthetic spinel at the Nantes Museum, from Wikimedia Commons<\/em><\/figcaption><\/figure>\n\n\n\n
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Spinel through history<\/strong><\/h2>\n\n\n\n

For centuries, spinel was confused with ruby and adorned royal crowns and treasures. Perhaps the most famous example is the \u2018Black Prince\u2019s Ruby\u2019, a red stone of over 170 carats set in the British Imperial State Crown, which is actually a spinel. In India\u2019s Mughal empires, enormous red spinels were engraved with inscriptions and worn as pendants, symbolising power and prestige. In medieval Europe, gems extracted from Central Asian mines were regarded as rubies. Only in the 19th century did modern mineralogy clearly distinguish spinel from corundum, revealing its own identity.<\/p>\n\n\n\n

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CC Spinel. 4.13ct and 1.83ct. Taken by Azuncha.<\/em><\/figcaption><\/figure>\n\n\n\n
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The major spinel deposits<\/h2>\n\n\n\n

Spinel occurs in several regions of the world, but certain deposits stand out for the exceptional quality of their stones.<\/p>\n\n\n\n