Saturday, September 20, 2008

Balas Ruby, Black Prince's Ruby and Timur Ruby

In ancient times red spinel was often known under the name "Balas Ruby", a name devised most probably from Balascia or Badakhshan in Northen India , where the the earliest gemstones came from. "Balas" could be also derived from Arabic word Balakhsh, which was itself derived from Balakhshan, as the early Arab gemologists knew that this gemstone was different from the ruby, while in the West, and until the 19th century, "Balas Ruby" referred to a variety of ruby that wasin fact a spinel.

Two famous spinels are in the English crown jewels - one is an oval gemstone in the Imperial State Crown and known as the "Black Prince's Ruby", and the other is 361ct gem known as the "Timur Ruby"on which are engraved the names and dates of all it's previous owners. These gemstones were thought to be rubies until 19th century. Other famous spinels are the spinels of the Wittelsbacher's crown of 1830, which were also thought to be rubies until recently

Monday, September 15, 2008

Rare large spinels from Mahenge, Tanzania

A remarkable discovery in Mahenge, Tanzania has produced an amazing selection of exceptionally large, clean, and highly saturated red spinels from one crystal.

As the large crystal had already been broken up along its fractures when we acquired it, we were unable to photograph it in its original form. The rough produced an outstanding assortment of fine top color stones. Singly refractive gemstones like diamonds, garnets, and spinels can be especially brilliant and a high quality top color red spinel is even brighter than the finest of rubies. Although Burmese spinels may occur in a comparable color, they are almost never available in large sizes and invariably much more expensive.

While stock markets have been erratic, prices of rare colored gems have been increasing steadily due to a limited supply from remote localities and strong global demand.

Monday, October 8, 2007

An enormous red spinel crystal weighing over 52 kgs may be the largest red spinel ever unearthed.

Mined at depth of 10 meters in a farmer's field in Mahenge, Tanzania, the pyramid shaped spinel crystal weighing over 52kgs was discovered by a group of miners in the alluvial deposit.

Mining in the area is normally conducted by loosely organized syndicates of small miners funded by local entrepreneurs. The discovery almost sparked a riot as hundreds of other diggers moved in for a piece of the action. After escaping into the bush on a motorcycle, the miner and his motorcycle driver were forced to lay low without food and water for several days before making their way on to Morogoro, and then to Arusha.

"When the stone finally arrived, the miner's legs were bloodied from holding the heavy sharp-edged rock on the motorcycle" - noted an observer from

The impressive crystal was the vibrant orangey pinkish red color that is considered to be top for spinel. Even though the yield is expected to be as low as 3%, the sheer size of the rough still translates into several thousand carats of gems worth several million dollars. After cobbing, the gemmy chunks were hand carried to Bangkok, Thailand for faceting. Although most of the stones are small, a significant number of stones ranging in weights between 5 and 30 carats have already been faceted and sold. One piece is expected to cut a near clean stone over 50 carats.

Monday, March 12, 2007

Forgotten jewel of the gemstone world

Spinel is the great imposter of gemstone history - many famous rubies in crown jewels around the world are actually spinel. In Burma, where some of the most beautiful colors are mined, spinel was recognized as a separate gem species since 1600 but in other countries the masquerade continued for hundreds of years. Historically, fine red spinels were esteemed as much as ruby, and sometimes even more. Next to ruby and the rare red diamond, spinel is the most expensive of all red gems.

Spinel is commonly found in alluvial gravels with corundum and also in association with gneiss, serpentine, calcite, dolomite, and garnet. Precious spinels appear strikingly clean and free of inclusions. The best proof of spinel is spinel and microscopic octahedra may be scattered in long chains and sinuous bands throughout inner stretches of the host crystal.