A RARE British-owned gemstone steeped in history and intrigue sold for a record price of $30,000 per carat today (24 September 2015) at Bonhams Fine Jewellery sale in London.

The previous world record price per carat for a faceted Spinel was $16,000 which was set in 2013.

This exceptional gem was bought by a private telephone bidder.

Bidding came from round the world via 18 telephone lines, online as well as bidders in Bonhams London New Bond Street saleroom. Bonhams CEO and Global Head of Jewellery Matthew Girling led the auction of The Hope Spinel, which can be seen here (Bonhams can send link on request).

The Hope Spinel was part of one of the world's greatest gem collections until its owner – London banker Henry Philip Hope – died in 1839. Set in a 19th century silver and gold brooch, the huge 50.13 carats octagonal-cut stone is the size of a small plum and of similar colouring with a splendid rose hue.

Until today, it has not been offered for sale since 1917 when it went for £1,060 – the equivalent of £80,000 in today's money.

Bonhams was expecting bids in the region of £150,000 to £200,000 for the treasure although bidding became fierce between a number of telephone bidders.

Jean Ghika, Director of Bonhams Jewellery for the UK and Europe commented after the sale: "We are delighted with the price it has made. It was an exceptional gemstone with a priceless provenance and these pieces just don't come to the open market often and when they do, they are hotly contested.

"Bonhams is honoured to have been chosen to handle the sale of such a unique and magnificent gem."

The incredible transparency and impeccable cut of the Hope Spinel means it is classed as an "exceptional treasure" - but its provenance is equally fascinating.

Very large historical specimens of spinels were found in the ancient Kuh-i-Lal mines, in Tajikistan. These include the Black Prince's Ruby and the Timur Ruby both in the Crown Jewels. Both are called rubies when in fact they are spinels.

Jean Ghika of Bonhams adds: "These historic mines are geographically difficult to access and by the 20th century they weren't used due to political reasons. Spinels of this size and quality are therefore exceptionally rare even without the provenance of the Hope Spinel."

The Hope Spinel was assessed by SSEF, a premier gemmological laboratory in Switzerland who have confirmed it is from these ancient mines and due to its exceptional transparency, flawless cut, beautiful colour and large size, it is classed as an exceptional treasure of nature.