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Natural diamonds - rough and cut


#1

Hello,

I’d love to learn more about natural rough diamonds and natural cut
diamonds. I really enjoy the different colors they come in, their
rough appearance and texture, the types of cuts they come in such as
rose cut or other antique cuts and the fact that they have all
different levels of clarity often viewed in one single stone. These
stones are interesting in that they are indeed diamonds but not what
most people think of as a pricey.

What I’d like to know is :

What to look for when buying a good quality versus a poor quality
natural diamond.

Prices for these stones seem to be all over the place and I’m not
sure why one stone may be triple the price to a similar much cheaper
stone.

What should one expect to pay for these stones?

Are inclusions acceptable and do they affect value?

Are some colors more valued than others?

How to work with these types of stones. Are they as hardy as their
more brilliant counterparts?

How do they get their colors?

Good sources for purchasing these stones.

Any other practical and sources of

Thanks for any and all advice!

Regards,
Chris


#2

Chris, you asked: “Are [diamond] inclusions acceptable and do they
affect value?”

Inclusions do affect value, but as long as they don’t threaten the
durability of the diamond or detract from its beauty, they are
generally considered acceptable. In fact, they can even be desirable
when they help prove that a diamond is of natural origin and
untreated. Some jewelers have even used garnet inclusions as a
selling point for customers whose birthday is in January by saying
that they are getting an added bonus of having their birthstone
within their diamond.

Regarding your other questions, most of them are answered
with-easy-to-understand language inmy “Diamond Handbook,” which is
used as a textbook for diamond courses in some colleges and fashion
institutes. For and reviews, go to
http://www.ganoksin.com/gnkurl/ep812e

Renee Newman
reneenewman.com


#3

Chris,

There is a lot to gemology, and what you are asking could fill
several books. Here’s a brief take on it: What I’d like to know is :

What to look for when buying a good quality versus a poor quality
natural diamond.

The typical 4 c’s — clarity, cut, carat weight and color —
generally determine price. In the case of colored diamonds, there
are preferred shades and different colors are less or more valuable.

Prices for these stones seem to be all over the place and I’m not
sure why one stone may be triple the price to a similar much cheaper
stone.

See above. Also, there is no law that says that some dealers will
not charge more than others for equivalent stones.

What should one expect to pay for these stones?

Diamond appraisal is a tricky and complex business. You need to have
the diamond graded (or grade it yourself) first and then you have to
have access to price research to establish a price. The Guide is a
pricing guide for diamonds and colored stones that is put out by
Richard Drucker. It will have updated prices (each quarter) on all
the gemstones and a reference manual with it that includes standards
for color and clarity grading. You can also find a couple of manuals
that teach diamond grading. I would check the on line GIA bookstore,
although I wouldn’t necessarily buy new from them. Check Amazon or
booksold.com.

Are inclusions acceptable and do they affect value?

Inclusions are a fact of life with diamonds. How “acceptable” they
are depends on their visiblity and how rare the diamond is. A deep
red or blue diamond that has not been treated is going to be worth
some pretty good money even if it is somewhat included. very cloudy
or included diamonds are downgraded considerably.

Are some colors more valued than others?

Yes, look into gemology texts and the Drucker’s manuals for the
specifics.

How to work with these types of stones. Are they as hardy as their
more brilliant counterparts?

All diamonds have the same hardness and cleavage. So yes, but you
can chip or cleave them in setting. If you are asking about cutting
them, that is a very specialized trade. There are a couple of manuals
about it, but it takes years to learn and thousands of dollars worth
of specialized equipment.

How do they get their colors?

Nitrogen (brown and yellow) and boron (blue) trace minerals and
plastic deformation of the crystal lattice in most other colors. You
need to consult a good gemology text for more info.

Good sources for purchasing these stones.

Check at gemology on line for further discussion and possibly
someone will have some sources. Colored diamond rough is going to be
pretty hard to find.

Any other practical and sources of

I think there is a diamond cutting manual by Basil Watermeyer. A
good place to ask further questions would be at the gemology on line
forum.

A couple of the world’s best gemolgists post there as well as folks
plugged into the rough stone market. Be aware that this is very much
a small niche where only a few have and many are not
disposed to sharing. Also, as I noted above, it’s a rather complex
subject that doesn’t have easy answers. You’ll need to study quite a
bit to know much about it.


#4

When listing diamond price factors, it is a good idea to include
transparency and treatment status with the 4 C’s.

TRANSPARENCY is the degree towhich a diamond is clear, hazy, cloudy
or opaque, whereas CLARITY is thedegree to which a stone is free
from external marks called blemishes and internal features called
inclusions. Two diamonds with the same clarity grade can have
different transparencies.

The treatment status involves whether the stone is treated or
untreated; and if treated, the type of treatment it has undergone,
e. g., laser drilling, fracture filling, coating, irradiation, high
pressure high temperature heat (HPHT) treatment. Untreated stones
are the most valued, and the various treatments affect price in
different ways.

It’s also helpful to divide “cut” into three components: SHAPE,
CUTTING STYLE, and CUT QUALITY because they each can have a separate
effect on price. In addition this ensures that the buyer won’t
overlook the importance of the quality of the cut.

Renee Newman
reneenewman.com