There
are some, including the former writer of this that make light of strain
in diamonds. It is also called Stress and occurs in about 40% of diamonds. It is generally more prevalent in pears, triangle shapes and marquise
shape cut diamonds than in rounds.
To a cutter strain
is of severe importance. Any cutter worth his salt will analyze the location,
color and amount of the strain before cutting a diamond. Strain sometimes also if evident around an inclusion in the stone
and shows up with tension marking, which sort of has an appearance of
a circle with a cross.
Is strain something
to be �terrified� of? No it isn�t. Industry perception is that if the diamond crystal
survives the cutting and polishing process it will survive normal wear
and tear. However being armed with the information is important to know.
What is Strain
Imagine a piece of
wood. It has a grain. So do diamonds.
Wood sometimes has knots. Guess what? So do diamonds.
Stress or strain in
a diamond is distorted crystal growth. The appearance is sort of like
the differences between straight graining is wood and that which curves
around.
Observing Strain
How can I see if my
diamond has strain. Strain isn�t visible to the naked eye or even under
a microscope or loupe. In order to see strain in a diamond it requires
examination under magnification view with crossed Polaroid lenses. The
lower lens is in a fixed position. The upper lens is rotated until the
background is the darkest. This is when the lenses become �crossed�. Strain,
when observed under magnification and crossed Polaroid lenses shows itself
in colors. Perhaps the colors that have the most significance
concerning durability is red or orange. Most commonly diamond exhibit
blue strain, or brownish to grayish shadowing.
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is a photo of observed strain in a
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| pear
shape diamond |
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Strain
in a round diamond |
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| Strain
with tension |
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Logical Analysis and Researching This Subject
The
approach of analysis is made in many various standpoints.
From
the cutter�s point of view, stones that have strain are more �challenging�
to cut. From a seller�s position,
it become a concern to purchasers that can make a consumer nervous about
buying a particular stone.
From
the independent gemologist�s viewpoint,
when, and if there is a potential for damage, he has a responsibility
to disclose this fact. The consumer who is dependent upon an expert opinion,
will be critically relying on getting complete information. Most seller�s won�t disclose the existence of
strain. It is a cumbersome and awkward characteristic for a seller to
soften it�s existence. It�s akin
to the relative softness by using the term inclusion
m instead of the term flaw which of course does have
a somewhat negative consumer interpretation.
For
a consumer who is considering purchase, since the existence of strain
is not disclosed, a diamond with strain and a diamond without strain is
priced the same.
Based
on the location, color and amount of strain� one must logically conclude
that a diamond with a potential hazard shouldn�t sell for the same price
as one that doesn�t.
In
my research of this subject I asked a great number of cutters, sellers,
other gemologists, and consumers for their opinion. All the cutters I
spoke to agree that strain can be a hazard, unless the cutter is selling
a stone that has strain. In this instance, their opinion changes to �
if the stone survived the cutting process (heat and vibration), it will
survive normal wear.
When
I�ve spoken to sellers about this, most don�t even bother to check if
the stone they are buying has strain present in the crystal. And if told
about it, they make light of it. So then I asked a second question, if
you feel it isn�t a problem, and you want the consumer to buy the stone,
why don�t you protect them by offering to replace the stone if in fact
it does break, or at least adjust the price.
I am told this is ridiculous, and isn�t an issue of importance.
Then
I spoke to an insurance adjuster who is also a gemologist that is credible
and knowledge. I asked him if in
examining damaged or broken diamonds if he has seen any evidence of damage
or breakage due to strain near the break.
I further asked if he had denied any claims due to this pre-existing
condition. He told me he hadn�t, as the company he worked
for wanted to not face a discord with their insured, but in an extreme
case he might.
I
have also questioned countless consumers about this issue, and 99% are
concerned. The really don�t understand why this fact is NOT disclosed
on major lab grading reports.
This
is a subject that there is still much to learn about it, so as more testing
results are gathered or facts relevant to improving the learning of this
issue, this article will be updated
and revised.
�
2005 � William R. Lieberum GG � All Rights Reserved � Duplication only
permitted by written permission
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