Diamond Jewelry King » stone

Diamond

King of diam — Mon, 21 Sep 2009 22:18:10 +0000

For thousands of years diamonds have been a form of decoration, currency and investment medium. Diamonds have risen in price over the years fairly consistently with inflation. At some points investment in the right stone would have returned a much better percentage than similar amounts of stocks, bonds or gold. On the other hand, an investment in the wrong thing or an investment made blindly because of lack of knowledge, can and in many cases has caused the buyer to actually lose money.

Remember, diamonds are normally sold on a retail basis. This is where you, the consumer, buy most stones. As one purchases stones of a higher quality and larger weight, stones that are designed for investment purposes rather than ornamentation, it is possible to actually buy at or near wholesale prices. When one goes to sell the stone, if one simply walks into a jeweler or New York-type diamond seller, one expects to lose from the retail price the stone may have been purchased at.

A number of factors establish the value of a diamond, one of which is the size of the stone. There are certain levels where the value of a high grade stone jumps appreciably simply because the stone is over this weight. In general, a large high-rated stone is worth logarithmically more than a number of small stones equaling the larger stone’s weight. It is, as one would expect, considerably harder to find flawless or near flawless large stones.

When the jeweler or professional goes to buy a stone there are several things he will evaluate in order. Generally the stone is graded using the four C’s of diamond grading. These are:

1. Clarity

2. Color

3. Cut

4. Carat weight

There are established methods and models for grading stones and one could reasonably expect to take a stone of a certain grade from one professional to another and come out with a similar rating. One should also remember this grading is subjective and there will be times when two accredited gemologists will give a different rating, possibly affecting the stone’s value, by hundreds or thousands of dollars to the very same stone. It is wise to be able to at least make a good amateur estimate of the various rating points on your own instead of having to blindly depend on someone you may not know.

Emeralds

King of diam — Sat, 19 Sep 2009 22:56:54 +0000

Emeralds are a green crystal of beryllium-aluminum silicate. The chemical formula is Be3Al2(SiO3). They are hexagonal prismatic crystal with a hardness of 7 1/2 to 8 on the Mohs scale. They are not tough stones and may be broken easily by mishandling or the use of severe chemicals or ultrasonic cleaners. If you own an emerald, be careful of it. Don’t wear it during sports. Don’t have a jeweler clean it in an ultrasonic cleaner as it may shatter.

Emeralds also break under applications of heat and should never be in a ring that is soldered. Under ultraviolet light they may fluoresceslightly, orangish red to red, or they may be inert.

Emeralds come from a number of sources. The best come from Colombia. These are the purest colored and generally the finest stones. The emeralds from Brazil are lighter, have more inclusions and are generally smaller than from other areas. Zambia, Africa, produces some bluish stones and some near-Colombian stones. Zimbabwe is home to a particular emerald known as the sandawana emerald which is generally small with a rich green color. Anything over 1/3 carat is rare.

South Africa produces some low-quality emeralds. Tanzania produces a few very good quality emeralds. Pakistan has just discovered some high-quality emeralds. Afghanistan tends to produce flawed but good colored emeralds. USSR does produce emeralds but doesn’t like to let them out of the country. Australia produces some dubious quality emeralds and North Carolina a few gems. Austria and India occasionally produce emeralds.

Emeralds are not unusual as the word emerald simply indicates an extremely nice version of a fairly common stone known as beryl. It is possible to buy something legitimately called an emerald for about $5 a carat. Obviously this is full of flaws, not transparent and so impure in color it looks more like jade than an emerald. They would never be sold in a jewelry store but emeralds do sell on TV and some of the better magazines for $5 per carat.

Gem quality emeralds range anywhere from $400 to $18,000 a carat, depending upon their quality. As the stones get larger, they become increasingly rare and sell for considerably more money.

Color is a critical factor in emeralds and constitutes about half of the stone’s value (clarity 30% and cut 20%).

Hue describes the primary color and any other colors in the stone. Most emeralds are green hued with a bluish hue also visible, especially the better Colombian-type emeralds.

Tone is the depth or darkness of the color as perceived by the eye.

Saturation is the amount of hue present in any given color.

Depending upon where the emeralds come from, they can exhibit a wide range of color; i.e., Brazilian emeralds are usually lighter toned and less saturated than their Colombian cousins.

The green in the emerald is caused by trace elements of chromium and/or bandium. If the color is very light green, the stone is more correctly referred to as green beryl, not emerald.

Emeralds are often oiled to help their appearance. Normally an uncolored oil such as Merck cedarwood oil is used. The stone may soak in the oil for several days and will actually take the oil in somewhat, helping bring out the color and “wedding” on some of the dry inclusions, making the stone look better.

If one finds an emerald that is mild in color or has a grayish hue, it is a good bet to soak it in oil a couple days and it may regain its green color, not to mention its value.

A more unscrupulous “improvement” is to use dye or oil with color in it. It is possible to influence the color of a stone by having it soak up colored oil.

Other problems with buying emeralds are the fact that there are a number of stones that look like emeralds and overlap colors. Tsavorite, a garnet found in Kenya and Tanzania, looks quite a bit like emerald and has a pure green hue, although it tends to be a little bit more yellowish and never has the blue hue of emerald.

Chrome tourmaline is another stone that looks much like an emerald with a moderately strong green color. Another emerald look-alike comes from Africa and is called chrome diopside. All these stones can, and are, sold as emeralds to the unwary.

Different emeralds from different areas tend to have individually shaped inclusions; i.e., slight pyrite inclusions are typical of emeralds from Colombia although they can be seen in stones from other sources.

A three phase inclusion that shows up under a 1 Ox or stronger microscope, which has a distinctly liquid area, a gas bubble in a solid square rock crystal, salt Iying superimposed on each other inside a jagged edged cavity, is typical of emeralds from Colombia and proves their natural origin.

Tropiche emeralds from Colombia sometime exhibit six fine radiating arms of black carbon inclusions, spoke-like in appearance. Another type of this stone has six arms of emeralds extending from the center of the crystal with a white shaped wedge area in between. When these stones are cut and mounted, they are valuable because of their inclusions.

Emeralds are subject to not only customs duty but market restraints as there is no OSO type organization supporting them. It is possible, if one is smart and has verification equipment, to buy emeralds in other countries, notably South America, and smuggle them to America for profit. Coincidentally, the areas one smuggles emeralds from are the same areas one smuggles cocaine from and these passport stamps tend to yell search me, search me. Some people even go to the trouble of swallowing and then recovering emeralds although obviously, we do not encourage or advise this dangerous practice.

Carat weight diamond grading

King of diam — Sat, 19 Sep 2009 22:21:15 +0000

The fourth and final C in evaluating a diamond for purchase is the carat
weight. The term carat is a reference to biblical times when diamonds were
compared against a carob bean because carob beans tend to have a uniform size
and weight. One carob bean became the equivalent of one carat. The carat is
still the primary unit of diamond weight used today. However, a carat is
further broken down into 100 sub units called points. One point equals 1/100
of a carat.
When you buy diamonds it is often mentally economical to break the price of
the stone down to a per carat basis. A rather crude example would be if you
were buying drugs you would break the price of a kilo down into a gram weight
to establish what you are actually paying per unit. The same is true in
diamonds. You should divide the weight of the diamond into the price to get
the carat weight.
The next thing to realize is that carat weights do not follow a linear
progression in terms of price. There are certain man-made break points in
diamond pricing. The first break is at .50 (1/2) of a carat. The second break
is at 1 carat and then succeeding breaks occur at each carat thereafter.
These breaks, although arbritrary, are valid and a diamond that is .52 of a
carat will cost considerably more than a diamond that is .44 of a carat. A
diamond that is over 1 carat, say 1.03 carats, will cost considerably more
per point or per carat than would a diamond that is .94. Because this break
is so critical, one should always see a diamond weighed in front of one on a
scale that has been verified by using an accurate unit of measure. In other
words, put a one gram weight on the scale and see if it actually reads one
gram.
Because of the price involved, these break points are quite important and one
does not want to pay the price differential for over a 1 carat diamond for one
that’s actually a couple points under. When it comes time for resale, the next
buyer will not be so generous in his consideration of the weight.
These price breaks are very substantial and are one of the few things in
diamond selling that is not subjective. As such they are quite evident in all
diamond sales. The difference per carat weight in a diamond that weighs from
1 to 2 carats may be as much as $1,000 per carat or more, on a 2 to 3 carat
diamond. This holds true on a 3 to 4 carat diamond also. One could expect to
pay not $1,000 more but $1,000 per carat more. This tends to increase as one
gets into the heavier weights and good grades of stones because the stones
become much rarer. It is much easier to find small good stones than it is to
find large stones of the same quality.
Wholesalers and for that matter, diamond retailers, buy their diamonds on a
per carat basis and if you are going to buy from anyone in the business, you
should consider the stone in that same light.
It is practically impossible to quote diamond prices in a paper like this
because they are subject to change and market fluctuations. Retail diamond
prices are also subject to seasonal conditions and one will find that holidays
and gift giving times such as Christmas tend to bring about severe prices from
retail outlets while the spring and summer months will often evoke a more
favorable estimate from a retailer who needs to make his rent that month.
Wholesale diamond prices should not change too much due to seasons or gift
giving times. Wholesale prices will vary when the market demands exceed supply
and also tend, as with gold, to function somewhat independently and opposite
of “soft” currency such as the dollar.
The price one pays is determined by how much the seller wants to sell the
stone and how much the buyer wants to buy it. Obviously in certain situations,
stones are cheaper than they would be in a high markup area such as with a
retail jeweler.
A stone may come with an appraisal sheet from one of the two gemological
societies recognized in America. This sheet, as we have seen, details a number
of qualities about the stone and will establish an appraised price. A couple
things one should be aware of about appraisals; the first is that they’re
invalid generally.
Appraisals are an instrument designed for insurance companies to establish a
possible price on a diamond that includes a number of factors such as increase
in value during ownership. The appraisal sheet will be inflated over the value
of the diamond. One never expects to pay full appraisal price for a diamond
and if one does, the term “saw you coming” falls quite aptly into place.
Appraisals also vary from person to person even with accredited gemologists.
The same stone can bring about two entirely separate appraisals that may
differ in value by hundreds or even thousands of dollars. Again, the appraisal
is a piece of paper that allows the insurance company to set a value on the
stone, not that the insurance company will necessarily pay off the appraisal
at full price either.
One cannot make a living by buying diamonds, having them appraised and then
reporting them to the insurance company for too long.
Appraisals, on a very general basis, tend to be nearly double the price that
a stone will actually sell for. This is a very wide statement and some
appraisals will, of course, be closer to the actual value of the stone than
will others.
Appraisals cost money and if you are good enough to sell the qualities of the
stone after a little bit of practice, your own word and your own peace of mind
will be more valid than a piece of paper. You are buying a piece of paper
that someone else may not want to buy.
One should actually consider that one is buying the stone, not a piece of
paper telling one how valuable the stone is. This could be compared to buying
a car because the owner wrote an article about how exciting the car was.
Needless to say one should base the actual purchase price on the vehicle
itself…
Reasons for getting an accredited appraisal are having the stone you want
insured, or when you go to sell the stone, having an appraisal that verifies
the stone’s quality to an unsophisticated buyer and that lists the price
considerably higher than you actually expect to get for the stone, which may
help sell the stone.
This is a nice line of thinking as long as you are the seller and not the
buyer. This is a buyer beware type of business and you should know what you’re
getting and should take all safeguards possible to insure you’re getting what
you think you are. If you’re buying in a slightly dubious situation and
perhaps are not as concerned with the stone’s pedigree as some people would
be, you should be prepared to never see the seller again and live or die on
your evaluation of the stone, not a piece of paper from an appraiser.
It should also be pointed out that in certain situations one would not want to
take a stone in to an appraiser. I will leave this to the imagination of the
reader.
Although appraisals are intended for an insurance company’s benefit, one
should realize that if an insured stone is stolen or otherwise destroyed, the
insurance company may want additional information regarding the purchase of
the stone along with an independent appraisal. There are exceptions to this
rule. If this stone was a gift or was left to one in an estate, obviously an
appraisal becomes the primary instrument of value determination and, as such,
is extremely useful to have on hand.
As a sidebar here, there are ways of destroying or damaging a diamond, even
though a diamond is one of the hardest materials known to man. As previously
pointed out, they are brittle. If you strike a diamond with a hammer, you’ll
dissolve it into useless industrial dust. If you touch a diamond to an
acetylene torch of significant temperature, you will observe an extremely
interesting and costly phenomenon where the diamond turns back into the same
black carbon that it came from.
Graphite, in other words. Once this happens the only recourse is to hope the
diamond was large enough to burn in the furnace and get some heat because
there is no way of changing it back quite as readily to its crystalline form.

Cut grading diamond

King of diam — Sat, 19 Sep 2009 22:15:55 +0000

Bear in mind also that a good diamond cutter can cut a colored stone in order
to make it appear whiter than it is WHEN THE STONE IS MOUNTED by doing a
shallower cut that’s more spread on the point where the facets come together.
This will make the stone appear less yellow, again only after it’s mounted.
This is another reason one should never judge a stone that is in a mounting
of any sort.
The cut of a brilliant diamond may be the most singular important consideration
in buying a stone within a set price range. Unless one is an expert and feels
his knowledge is good enough to override general public consideration, there
is only one cut to consider and that is the “brilliant” cut. Brilliant cut is
a modern cut that is a completely round stone designed with 58 facets to
maximize light reflection and “fire” within a diamond.
There are a lot of stones still around which have what is known as a European
cut. This cut was done in the 1920′s and before and does not compare in value
to the modern brilliant cut. The old cut or European cut stones were cut
before exact ratios and angles were established and understood by the gem
cutting society and, as such, do not maximize the reflecting and refraction
qualities of the stone. European cut stones such as those purchased at pawn
shops and estate sales, are much harder to resell and do not offer the
liquidity of a brilliant cut diamond.
There are other popular modern cuts such as the marquise, the oval and the
pear which attract some buyers when designed for jewelry, due to their unique
appearance. These cuts do not reflect as well as the brilliant cut and are
rarely seen in investment quality jewelry. Again, the fancier cuts will be
on the average much harder to sell (definitely harder to sell to a dealer)
than is the round brilliant cut stone.
Fancy cut diamonds have fewer angles cut to what is known as the “critical
angle” and, as such, cannot be as brilliant as a round cut stone. The fancier
a stone is, the more it differs from a brilliant cut, the greater the loss in
light reflection will be.
Another phenomena to be aware of in fancy cut stones such as pear shapes or
marquise shapes, is something called the bow tie effect. This is a dark,
cloudy area across the upper portion of the table on these stones. It is a
quality inherent in the cutting and looks like a cloudy bow tie across the
reflecting portion of the table. This obviously lowers the value of the stone
considerably and, if one is thinking about a fancy cut stone, this effect
should be taken into consideration.
Fancy cut stones have only two bottom facets as opposed to the eight found in
round cut stones to reflect the light back. While they still may appear to be
fairly brilliant, the refraction, the fire of the stone, will suffer
critically. This loss progresses from the marquise cut through the straight
cuts such as the emerald cut diamond. These straight cut stones suffer a great
light and fire loss and are not nearly as valuable as the same stone would be
cut in a brilliant cut.
An uncut diamond is normally sawn or split into two or more stones as decided
by the diamond cutter. It just takes a simple error here to completely ruin a
valuable stone and turn it into nothing but dust. Now you can understand the
hypertension rate among diamond cutters and airport controllers…
Once a rough diamond is split, the diamond cutter then decides how the stone
will be laid out and cut. This operation means that a certain portion of the
diamond will be ground off and lost and so this cut plan becomes an important
step in finishing the final stone.
The first step taken by the diamond cutter is to girdle the diamond. This
process of girdling establishes the size of the stone and puts a “waste” on
the stone (see the diagram). If a stone is poorly girdled, it will not appear
completely round when viewed with the jeweler’s loupe or microscope. A round
brilliant cut stone should be perfectly round and symmetrical.
Other mistakes in girdling will produce flaws that manifest themselves as a
razor thin girdle which is prone to chipping or breaking (even though diamonds
are extremely hard, they are brittle and can be chipped or shattered in thin
areas). A too thick girdle takes away from the brilliance and fire of a stone
and indicates a poor job on the part of the diamond cutter.
A diamond cutter cuts (in a brilliant cut) 58 facets all done on exact angles
in exact positions in order to let the diamond reflect as much light as is
physically possible. The brilliant cut stone has 16 facets on top and 16
facets on the bottom that reflect the light and give the stone its cut. Each
facet is cut on a unique angle and is exactly straight when viewed with other
facets in order to maximize light reflection.
When you view a brilliant cut stone, around the table of the stone you’ll see
the kite and the topmain facets. These facets are the areas that allow the
light to come through to the viewer. Beneath these you have eight star facets
and then 16 upper girdle facets before you reach the girdle itself. Beneath
the girdle you have an additional 16 lower girdle facets. All these ancillary
facets contribute to the light reflection through the kite and top main facets
and the table portion of the stone.
What is the advantage of the 58 facet brilliant cut stone? What does one
expect to see when viewing a diamond? There are two qualities that make a
diamond attractive to the eye. The first one is known as life and indicates
the amount of light that is reflected back from the diamond to the viewer.
The second quality is known as fire, which is an indication of the amount of
refraction from the facets and split into colors as in a prism effect.
Besides the 58 facets, a number of other factors contribute to the perfectness
of a brilliant cut stone. The stone’s table should be 53% of the area of the
stone. While the ratio between the depth of the stone or the length of the
stone if you view it from the side, to the spread of the stone which is the
maximum diameter of the girdle, this ratio should be 60% depth to spread.
The angles on a stone must be cut exactly to critical angles. Any deviation
will produce a less than perfect reflection of the light waves entering the
stone. A jeweler will have special gauges to measure these angles. These
gauges are available but they are expensive. Or one can buy a loupe that is
marked with angle markings.
When angles are viewed through this loupe, they can be accurately measured .
The first measurement to take is the degree of the angle from the table to the
girdle of the stone. This is known as the top critical angle and should be 34
1/2 degrees. Underneath the girdle, the bottom angle from the girdle to the
point of the stone is also a critical angle and should be cut at 40 3/4
degrees. A further measurement is that the girdle should be about 1% as thick
as the diameter of the stone, although this is not quite as critical as the
other measurements and can be judged by the eye after a bit of practice.
A stone which is not cut with the critical angles in the right degree, will
either be shallow cut or deep cut and will not reflect the light back through
the center of the stone (the table of the stone) with the same brilliance as
a stone that is cut to the correct angles.
If the stone is shallow cut, the light will reflect off the edges of the stone
but not through the middle. If it is cut too deeply, the center of the stone
will appear to be dark and it is called “heavy.” In the past some cutters cut
the upper angles at a less than 30 degree cut. This “spread cut” helps hide
deficiencies in a stone but makes the girdle angles sharp and likely to be
broken or chipped and the stone is not as valuable as a normally cut stone.
If the correct tool for sizing angles is not available, one can estimate that
if the table appears to be larger than it should, and the width to height
(that is the depth spread ratio) is below 60%, one can assume that the
critical crown angles are shallow.
It is possible to polish a diamond to a high degree to compensate for shallow
or deep cut angles at first glance and make the stone appear to be more
brilliant than it, in fact, is. If the stone is chosen for investment quality,
a measurement of these angles is almost essential .

Color rating diamond

King of diam — Sat, 19 Sep 2009 22:10:16 +0000

The second C used in rating diamonds is color. Diamonds come in literally
every color in the rainbow and while a few specialty colored diamonds are
extremely valuable because of their deep hues and unique color characteristics,
these are the exceptions rather than the rule. In general, the closer a stone
is to possessing no color, that is, to being colorless, the more the stone is
worth.
In order to establish the transparency or lack of color in a diamond, the
loose stone is placed on a pure white background under a white light. There
are special lights sold with adjusted color temperatures for this viewing or
some people prefer to use the soft north sunlight when trying to view the
color of a diamond.
In color rating as in clarity rating, the dazzling brilliance and fire of a
diamond are the viewer’s natural enemy. They will confuse the eye and care
must be exercised to not become jaded or tricked, but rather to view each
characteristic individually and in comparison to other stones or photographs
of stones.
The most accepted color grading system is that again of the GIA. Their system
is judged by using a series of master stones sold by the GIA or their
representatives that establish hues and tints and can be laid side by side
with the stone in question in order to view how “white” the stone really is.
If at all possible, it is certainly worth one’s time to visit a large gem
dealer with the intent or apparent intent of purchasing a goodsized stone and
ask to see a master set and become used to judging the color on several stones
until you have a feel for the concept of whiteness, transparency and hues.
Technology has now produced a practical and inexpensive (comparatively) method
of possessing your own diamond master stones. These stones are available in all
colors D through Z on the GIA scale and are excellent to have on hand to
compare with any other stone you may be considering purchasing in order to
rate the new stone. These stones are color correct because they’re created to
be exactly the color they’re supposed to be.
How can this be cheap? The stones are not diamonds. They’re CZ’s, cubic
zirconia. These CZ stones look like diamonds, act like diamonds, smell like
diamonds and can be matched to a real diamond in order to compare colors with
an extreme degree of accuracy.

There’s also a device known as a color meter which electronically measures the
color or lack of color in a stone. This meter is quite accurate although
fairly hard to come by unless one is a member of the Gemological Institute of
America.
The GIA color rating system has been established using alphabetical
nomenclature. The stones are rated from pure (totally colorless) down through
a sliding scale to yellow, which is the least valuable stone. The GIA color
rating system starts with the letter D and progresses through the alphabet as
shown below to Z, which would be very yellow.

A B C D E F ) Colorless
G H I J ) Near Colorless
K L ) Faint
M ) Yellow-White
N O ) Very Light Yellow
P ) Light Yellow
Q ) Yellow
R S T U ) Light
V ) Yellow to Fancy
W ) Fancy
X Y Z ) Yellow

After the letter Z, indicators are used to suggest the stone is more valuable
because of its hue; i.e., a “fancy” color. As you can see from the above chart,
D, E and F stones are considered completely colorless. G, H, I and J are near
colorless stones and take a lot of practice for the amateur to see any color
at all, while after J the stones begin to pick up a small tint of yellow that
is noticeable to practiced gemologists.
To correctly grade a gemstone, the stone must be loose, not in a setting,
should be on a perfectly white background, should have a white gem quality
temperature light and should be viewed from the rear of the stone. In other
words, the stone should be upside down Iying on its table. It is also
extremely helpful to have stones of known color grades nearby for active
comparison.
Never attempt to judge the color of a diamond when it is set in any kind of
setting, be it earring, ring, or whatever as it is strictly impossible to
judge the color of a mounted stone that is taking on hues and tints from the
mounting itself.
Color is a very important consideration in choosing investment quality
diamonds and, in fact, the differences in large sizes such as one carat and
over from a D to an E color (again these are the top rated stones and are both
considered colorless to the naked eye) can be double the price between these
two grades.

Clarity of diamonds

King of diam — Sat, 19 Sep 2009 22:03:20 +0000

The first C is clarity. This is not the most important but is generally the
first item looked at in a stone to be rated. Clarity does not refer to the
concept of “being clear” with reference to a diamond. Clarity refers to the
purity of the stone and lack of visible defects.
These defects or flaws or as they are properly known, inclusions, may manifest
themselves as dark, black carbon spots, white carbon spots, small cracks,
“clouds”, feathers, or other areas of visible diffusion within a diamond or on
the surface of the stone itself.
A truly flawless stone, one without any spots, cracks or inclusions, is very
rare and extremely valuable. One can expect to find some flaws in most stones.
The type of flaws, size of flaws, and location will have an effect upon the
stone’s value. It is important to learn how to judge a stone for clarity.
The Gemological Institute of America (GIA) has established a rating system for
expressing the clarity of a particular stone. This rating system is based on
the use of initials and numbers and goes on a one to 10 oriented system
wherein 10 would be the best stone and one would be the worst stone.
This system is not expressed in simple numbers but with words and initials to
further establish the rating scale. The scale is as follows:

10 – Flawless – no blemishes can be found.

9 – VVS-1 – no flaws inside the table. Possible very small internal
flaws outside the table. If any external flaws are present,
must be very minor.

8 – VVS-2 – very difficult to see flaws with 1 0x magnification power
employed.

7 – VS – 1 – flaws readily seen using 1 0x glass but almost impossible
to see when the stone is viewed from from the back.

6 – VS – 2 – the back looking down through the stone.

5 – Sl – 1 – flaws unable to be seen with the naked eyes but quite
apparent using 1 0x magnification.

4 – Sl – 2 – inclusion may include carbon spots or clouds or feathers
underneath the table or larger flaws outside of the table.

3-1 – I-1 to 3 – this is the least valuable group. They are heavily flawed
and the flaws can be determined with the naked eyes. There
are going to be internal flaws inside the table, maybe
clouds, groups of carbon spots, feathers and/or cracks
that can be seen with the eye.

VVS – Very, very, slightly imperfect
VS – Very slightly imperfect
Sl – Slightly imperfect
I – Imperfect

A flawless stone is simply that. No flaw can be found even with the use of a
10x jeweler’s loupe or 10x microscope. As you go down the scale, the VVS-1 may
have one very small inclusion, generally not in the table (which I’ll cover it
later in the file) portion of the diamond but possibly on the edge. Again,
this flaw is seen only from the front and only on using 10x magnification. It
should not be visible to the naked eye.
As we get into VVS-2, there may be more than one flaw wlth magnification but
they’re still extremely small. One small inclusion may be in the table area of
the diamond.
Into the VS grades, the flaws become larger and more prominent than their VVS
cousins. VS2 may have larger flaws or a number of small spots possibly located
in the table of the diamond that group together and are almost considered one
flaw. They are generally in the same area.
When we talk about 10x magnification, this can be in the form of a jeweler’s
loupe which is a fairly inexpensive must-have item for anyone serious about
stones or a step upward which is the two eyepiece (stereo) microscope, which
many jewelers will have on the premises and will let one borrow when perusing
their stones.
It is wise to always make sure that the magnification device employed is 1Ox.
This is the standard and any variation from this will affect the rating of the
stone to a great degree.
Note that flawless VVS and VS rated stones are rated when looking at the stone
right side up with a 1 Ox magnification device. If you pick up a stone that
supposedly falls under one of these ratings and you can see inclusions with
the naked eye, you’re not looking at a stone that is properly rated.
An Sl-1 rated stone will have inclusions that are very obvious under 1Ox
magnification, but should still be borderline visible or not visible when
viewed with the naked eye. The Sl-1 stone may have these borderline visible,
small dots or inclusions in the table or edge of the stone. An Sl-2 rating
will have larger flaws and probably more than one. These will be easily
visible to the naked eye.
In the I grades, the stones can be considered either quite flawed or imperfect.
Flaws are probably inside the table. There may be flaws of more than one
variety, clouds, cracks or groups of black or white carbon spots will be
visible. This last group of stones obviously are the least valuable and the
least interesting for anyone trying to convert from cash to gems and back
again.
Looking backward we can infer several things, the first of which being if you
can spot a number of inclusions without the use of magnification device, the
stone is going to be graded 1, whether l-1, I-2 or l-3 is open to some
subjective effort, but it will be an I rated stone.
If you can’t find flaws with your eye alone but they do become visible when
using a loupe, one can assume that the stone is an Sl rated stone.
The differentiation between an S stone and a VS stone is that in a VS stone
inclusions may not be seen extremely clearly even with the loupe. If the stone
is turned over and laid on the flat front part (the face of the stone – this
is the table) and one views down from the back of the stone where all the
facets come to a point and the flaws are more readily seen here, one can
assume it is a VS-2 or above rated stone.
Note this viewing is done under white light and with the stone loose. It is
very difficult to judge any of the 4 C’s when the stone is mounted. Mounted
stones are not generally considered for investment grade purchases. The stone
should be loose and one should be able to turn it freely.