Black Star of Queensland
Came across this Toronto Star news article recently about the “Black Star of Queensland” to be shown at the Royal Ontario Museum from June 2007. See the ROM press release for more about the upcoming exhibition.
This is the first time that this rare beauty has been on display since 1969. The black sapphire was found on the Queensland gemfields on Klondyke ridge in 1935 by 14 year old Roy Spencer and supposedly used as a door stop for many years by the father Harry Spencer (source Gemfields.com).
The rough crystal weighing an incredible 1165 carats (over 230 grams) was kept in the family for some years but was purchased in 1947 by the Kazanjian Brothers for almost $18,000. Harry Kazanjian studied the stone for some time before cutting it into a 733 carat star sapphire - at the time of cutting, the gem was valued at $1 million dollars. This was a good investment in more than monetary terms as the Kazanjian family said that it brought them good luck and held on to the gem for many years because of its beauty. When purchased by the present owners in 2002, the stone was valued at more than $100 million.
Star sapphires have been highly valued by many cultures as a “stone of Destiny” with the three bands of the star believed to represent faith, hope and destiny. The English explorer Sir Richard Francis Burton always carried a large star sapphire as a talisman to bring him influence and good luck in his travels. Star sapphires were also believed to help ward off ill omens and the Evil Eye.
The star phenomenon in sapphire (and other gems) is known as “asterism“. Although diffused star sapphires are widespread in the market and very cheap, good quality natural star sapphires are rare and accordingly command a premium price. As always, price will be governed by colour, clarity, size and quality of the star – smaller opaque types can be very affordable while superior quality specimens will be priced accordingly.
Diffused star sapphires are quite easy to spot as while the star is usually very distinct, it has an artificial look that is quite obvious. A natural star will seem to float inside the stone with a life of its own – beautiful and precious. See this thread on the Gemology Online forum for some spectacular examples of asterism in a variety of gems.