Wednesday, June 25, 2014

Rhi Rhi Rocks Rhodolite

Pop celeb Rhianna adds just enough color to snazz up her otherwise subdued outfit with a prominent rhodolite garnet and diamond ring. Good choice, this big rock.

Rhodolite garnet is a much sought after deep scarlet hued garnet jewel. Collectors swoon over these big rocks because this garnet variety tends to be relatively clean even in large carat sizes. Because of that, designers take boldly imaginative liberties with designing around these jumbo stones; knowing the view inside the stone will be as stunning up close as it is from afar. But it's certainly not just a recent designer fave. 19th century Russian designer Faberge made quite a few jazzy brooches from Rhodolite in his day.

Originally harvested in the US, in regions like North Carolina and Georgia, this gem variety is now commercially recovered from deposits in exotic East Africa and East Asia.

Garnet and diamond ring by IVY NEW YORK: Courtesy D'Orazio & Associates

Thursday, May 15, 2014

What's With Kashmir Sapphire?

28.18ct Kashmir sapphire sold at Sotheby's for $5.1M in April, 2014
Sapphires are a beloved precious stone. Britain's queen-in-waiting Kate's engagement ring is a sapphire and diamond creation. And it's not even the most coveted sapphire type, since those from Kashmir are considered the most valuable and rarest in the world.

Kate's ring is a valuable one of course, owing to its quality and provenance. Prince Charles paid about $45,000 US for the ultra blue sparkler in 1981. Princess Diana’s dazzling sapphire engagement ring now graces the finger of daughter-in-law Duchess Kate of Cambridge, and is worth about $480,000 US today, more than 10 times of its original purchase price.

But all things being equal, serious collectors go long for Kashmir sapphires which are all but mined out today. They originated in super high altitudes at mines deep within remotely accessed Jammu and Kashmir region at the northernmost tip of India.
Red area show Jammu and Kashmir atop India
But the difficult recovery is not all that drives their value. Geology plays a huge roll in a gemstone's appearance. What they are composed of, and the terrain which produced gemstones all contribute to their individual look. In the case of Kashmiri sapphires, collectors are enamored with their rich deep (but not too dark) blue and an almost indescribable velvety appearance, according to some. This soft and sumptuous appeal is the result of microscopic rutile (another mineral) inclusions. The inclusions appear like tiny threads or strands, and are referred to as silk.

Micro-image of rutile silk in sapphire Courtesy GIA
While you may not see it with the un-aided eye, this tell-tale trait keeps Kashmir sapphire in the most-wanted short list of world class gemstone collectors everywhere. 

Saturday, May 10, 2014

Water World of Gemstones

Aquamarine Literally Means Sea Water
Actress Jessica Biel wears Tiffany aquamarine and diamond jewels to the 2014 Academy Awards gala

Aquamarine is a much beloved gemstone that boasts collectors going back eons. While its traditional devotees are legion, it still finds a fan base in modern  jewelry lovers. Its pastel hue makes it a great companion for just about any wearer's skin tone . . . or even wardrobe choice for that matter. 

Aqua is a variety of the mineral species beryl, which also includes emerald and heliodor, or golden beryl. The rare cherry hued bixbite is also a beryl. Depending on other elements mixed into the beryl mineral in its formative stage, a different color will result.

Biel's close-up on her Tiffany aquamarine earrings
Aquamarine is generally a clean mineral, free of many natural inclusions that would detract from its beauty. Notice that the aquas shown here are large in size but more importantly they are shaped into emerald cuts. This cut is only used (for pretty much any gemstone or diamond) when the stone is clean, and can take the scrutiny of a close inspection.

Aqua is found around the world. Here's a rough crystal specimen from Pakistan.

If you like your gemstones large, sashay on down to Brazil, where the most massive aquamarine crystal ever was unearthed  in Minas Gerais, Brazil in 1910, weighing over 110 kg. Its dimensions were 48.5 cm (19 in) long and 42 cm (17 in) in diameter. That's a lot of watery-blue!