The World's Most Useful
Gem & Jewelry Monthly Newsletter
Written by Carolyn Doyle for customers of
The Dorado Company
and other visitors to the
azgem.com website who subscribe.
Share this newsletter with friends and co-workers by printing or forwarding it to them in its entirety.
Sign up for a free subscription to the AZGem Gems monthly newsletter.
Back issues of the
AZGem Gems newsletter can be accessed by clicking
Usable Gems... and a little opinion.
Gemstone rough is the subject of this month's
Specifically, she asks... "I've read in your
newsletter where you speak of gemstone rough. How is that different from the
gems you sell?"
Think of it as "before and after"
Gem rough is the gem crystal as it comes from the mine,
before it is fashioned into a faceted or cabochon cut gem.
Gem rough is a term usually applied to colored gems such
as emerald, sapphire, and in the case of the photo above, aquamarine. Diamonds
and diamond rough are generally referred to by those names.
Gem rough comes from the mines in a wide variety of
qualities and sizes, as you would expect. Quality and size can be relative to
the gem involved. For example tsavorite (the beautiful rich green variety of
garnet usually occurs in sizes under two grams. Colors can range from emerald
green to a blackish green.
The miner is the first player in sorting and grading gem
rough. Even parcels of "mine run" gemstone rough is graded by quality,
and possibly by size.
The general grades of gem rough are:
The Dorado Company was (until recently) involved in gem
mining in Madagascar. We are currently working to partner
with the owner of several existing gem mines in East Africa.
Our interest is in facet grade gem rough. Lower grades of
rough are sold off locally.
The larger the piece of rough, and the more pleasing the
color, the more valuable it is to a gem cutter, simply because of the finished
gem that can be produced from that piece of rough..
Many types of gem crystals can grow to large sizes.
Amethyst, citrine, spinel, and aquamarine are examples.
Clarity is also important to the value of a finished gem,
and therefore to the gem rough that the cutter starts with. Inclusions such as
veils, needles, and small crystals of other minerals must be eliminated in the
cutting process to the extent possible.
Amethyst and many other gems with eye-visible inclusions have a
greatly diminished value.
Inclusions are more acceptable and expected in some other
gems such as emerald. This is because emerald crystals generally occur with many
inclusions. The demand and market value of emeralds dictates that gems with some
inclusions are accepted. Even here, the prominence of inclusions impacts the
value of the finished emerald.
Cutters are looking for other good characteristics in the
gemstone rough they buy and cut. In addition to the size of the rough, cutters
evaluate the shape of the piece of rough. A "chunky" shape generally
yields a larger finished gem to the cutter.
Before faceting a piece of rough, the cutter will "preform" the piece by
grinding away inclusions and voids near the surface of the piece of rough, and
give it the general shape of the finished gem.
The piece can then be faceted
and polished to yield a beautiful finished gemstone.
Gem Industry News...
478 Carat Gem Quality Diamond
Gem industry news sources are reporting the discovery of a huge diamond
crystal of exceptional quality.
Miners in the Kingdom
of Lesotho have found one of the world's largest diamonds, a near-flawless
white gem weighing nearly 500 carats.
The diamond was reportedly discovered in the Letseng
Mine on September 8. It has been analyzed by experts in Antwerp and found to
weigh 478 carats, with very few inclusions and of outstanding color and clarity.
The company said "It has the potential to yield one
of the largest flawless D color round polished diamonds in history," the
mining company said.
The Letseng diamond mine is the world’s highest
operating mines, located at approximately 10,000 feet above sea level. The mine
is a 70-30 partnership between Gem Diamonds the government of Lesotho.
Letseng is one of the most productive mines in history.
Four of the world's 20 largest rough diamonds have been found at this mine,
including the three largest found in the last 100 years.
Before the piece of rough is cut into gems it is hard to
value. A similar weight stone with lesser-quality color and clarity has recently
sold for $12 million.
The world's largest diamond is the Cullinan, discovered
in South Africa in 1905. It
weighed more than 3,100 carats before it was cut into more than one hundred
The Letseng Mine is 70 percent owned by Gem Diamonds
Limited and 30 percent owned by the government of Lesotho.
An ailing economy is an opportunity for independent jewelry dealers.
We all know the economy isn't as poor as the news people indicate, as they
focus on the worst of it. Our own, and our neighbors circumstances are a better
People still want and need jewelry. Gift occasions, people building and
refreshing their wardrobe, and see it - like it - buy it purchases are
all sales opportunities for you.
An ailing economy isn't a deal killer when you offer quality, service, and
Do you enjoy jewelry and gems?
Do you enjoy talking with friends and co-workers?
Could you use an extra income source?
Take a look at our great
Want to change the e-mail address
at which you receive this newsletter?
Want to (gulp) unsubscribe?
me an email
and let me know
what you want to do.
The AZGem Gems Newsletter is now distributed
through RSS, as well as by e-mail. Use the appropriate button below to
add the azgem.com feed to your RSS service.
Subscribe to my RSS feed
an RSS feed?
AZGem.com is the Web presence of:
The Dorado Company
P.O. Box 8232
Scottsdale, AZ 85252-8232