For centuries, dealers relied on a simple visual test to determine what to call a colored stone. There are a couple of basic reasons for that; the foremost being that there were no reliable scientific methods of separating look-alike gems until the late 19th to early 20th century. To complicate matters, some similar color gems were found side by side in the same deposits or near each other in certain geological regions.
So, was it green? That’s an emerald. Cleopatra was said to love this verdant stone so much that she had her own emerald mines. Trouble is, some of those green stones were actually peridot which is also a fabulous stone - but it’s not emerald.
Aficionados are familiar with the story of the Black Prince’s Ruby, an irregular cabochon shaped red jewel which is the centerpiece of Britain’s Imperial State Crown. It’s one of the UK’s oldest gems of the Crown Jewels dating back to the 14th century. It has an estimated value today of around £10M. Trouble is, it’s not a ruby at all, but a mammoth red spinel. The same can be said of other crown jewels in royal vaults throughout Europe - their ruby crown jewels are actually spinel.
Centuries ago, ruby and a red spinel found side by side in the same deposit were all labeled ruby. And strangely in those earlier times spinel was esteemed higher than diamonds because of the audacious hues, luster and of course its hardness that takes a magnificent polish.
Now that we have scientific aids to separate gemstones with certainty, we understand that ruby is an aluminum oxide material - and spinel is a magnesium aluminum oxide - but you couldn’t tell that simply from looking at them, could you?
The Hope Spinel, so named because it was once owned by British collector Henry Phillip Hope (for whom his Hope diamond was named) crossed the auction block in 2015 at Bonhams London. The rare and rosy 50.13 carat emerald cut spinel shattered its pre-sale estimate of $300,000 US, earning $1.4M US from the winning bidder. The Swiss Gemological Institute called it an ‘exceptional treasure’ owing to its flawlessness, transparency, cut and sheer size.
Spinel is now being used by top-tier designers in their couture collections. The stone is produced in other fine colors besides red too - violet, green, blue and black for example.
Spinels have come into their much-earned place of pride today and consumers are responding.