Thursday, September 29, 2016

Greener Than Envy

I have a soft spot for green diamonds. There are so few of them, that most people have only seen them in photos.

natural green pear shaped diamond

Dresden green diamond

Take the Dresden Green diamond for instance.
Well . . . actually you can't take it. This robin's egg sized green whopper has lived in Dresden, Germany for the last few hundred years. It is about 41 carats in size but valuers claim it likely weighed closer to 100 carats in the rough.  This rare stone is naturally colored of course. When it came on the scene in 1722, enhancement capabilities did not exit for inducing color in a diamond.

Like some genuine green diamonds on the market, the Dresden green diamond obtained its apple green tint from natural exposure to radioactivity underground.  Since that is what happened to earth mined diamonds resulting in their green hue, modern methods in the lab can also create green stones after subjection to irradiation.

All good. Still I came across some interesting stones recently---green moissanite which gives a pretty good rendition of the sparkly green  story,

green moissanite ring
Moissanite is a manufactured stone made from silicon carbide--the stuff used in manufacturing LED light bulbs. As a diamond alternative it's hard, durable and less costly than its diamond counterpart. It's actually more brilliant than a diamond,  yet it's luster is vitreous compared to diamond's adamantine luster. It's pretty straightforward to separate moissanite from diamond by gemologists owing to moissanite's double refraction.

Now that moissanite is produced in color, I'm thinking it's an interesting stone in its own right.

Moral of this yarn is if you get bit by the green diamond bug, you actually have a few options that make it affordable to collect.. The Dresden will never be in someone's private collection. Many certified natural green diamonds also are outside most people's reach. But irradiated natural diamonds are affordable in the enviable hue. And now that moissanite offers greenies to boot, well, it just widens the field even more doesn't it?

Thursday, September 1, 2016

Twinkle Twinkle Little Stars

We love gemstones for their color, and sometimes surprisingly unusual hues, and even their rarity. Here's one more thing to love about precious stones. Occasionally a corundum (that's sapphire and ruby you know) is formed with natural needle like inclusions deep within the crystal rough.

Robert Procop star ruby ring

Looking Deep Within
Clever cutters recognize these desirable traits and exploit the stone's special inclusions by cutting the gem en cabochon instead of faceted. The result? The hidden needles emerge in a star-like pattern across the top of the domed jewel.

4-6-12 and Wiggly
They are then called star stones--as in star ruby or star sapphire. The rays are often 6 coming down from the top center of the polished dome of the stone. But a stone can have 4 rays, even 12. After all this is a natural occurrence we're revealing, so the variety is pretty individual.

12 ray black sapphire
The Straighter the Better
The straighter and sharper the rays, and the farther they go down the side of the cabochon, the more value they contribute to the stone. Wavy rays or shortened rays lessen the value of a star stone but nevertheless the stone is still a bit rare and certainly individually distinct.

wiggly-wavy 6 rayed star Lavender sapphire Art Deco period

Look-a-Likes are Loverly
As with all genuine stones that are coveted, their desirability often generates manufactured look-a-likes.Such is the case with star stones. From the 1950s through the 1970s a created stone called the Linde Star sapphire was made. Essentially its star was fabricated onto the created stone. They are still collectible and hold a certain charm today for collectors.

Linde Star sapphire circa 1960

So whatever star you are wishing on--whether one with 4 or 6 or even 12 rays--whether man-made or earth grown--you'll find these twinkling star stones are guaranteed to make your jewelry wishes come true.

Sunday, August 21, 2016

Granny's Chips

Britain's Queen Elizabeth II has an empire full of jewelry--and it's the most expansive in style, gem types and shear quantity. It's believed to be the most extensive jewelry collection in the world. And fortunately the world gets a glimpse into her bijoux from time to time when she wears them in public. But it's said that she wears her beloved jewels everyday in private too. Why on earth not?

The Biggies
The biggest of the big are lovingly and cheekily referred to as "Granny's Chips" and what chips they are. Look at the closeup of her brooch fashioned from the 3rd and 4th largest stones of the Cullinan diamond. This historical stone was found in the earliest part of the 20th century. It was over 3,100 carats when recovered at the Premiere Mine in So. Africa.

Real Cut Ups
Originally, these, called the Cullinan III and Cullinan IV were set in Elizabeth's grandmother's coronation crown. As you see it here, the 158 carat piece is fashioned into a stunning brooch.

"Well, how big is that," you're wondering? Let me illustrate.

Will that do? Oh that will do nicely, thank you.