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DIAMOND EDUCATION
Diamond Buying Guide - what to look for
when you are shopping for loose diamonds.
Introduction:
Over the next few pages we will attempt to educate and inform you about diamonds
and the 4c's. We will try to give you a basic understanding of what to look for
if you are shopping for certified loose diamonds, but not quite sure what types
of diamonds you should be looking for. The next few pages will illustrate the
4c's of diamonds, including definitions for Cut, Color, Clarity, Carat, as well
as Certification, and caring for your diamonds. There is also a glossary of diamond
terms incase you get stuck on certain diamond definitions.
Diamond Education:
When you have finished reading the following diamond information you will have
a better understanding of diamonds and you will be much more confident
when searching through our large database of certified loose diamonds.
The following diamond information is meant for a novice or a person with
little or no understanding of diamonds. If you need more specific advice
or information please don't hesitate to give us a call and our experienced
qualified jeweller can answer any addition questions you may have.
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DIAMOND CUT DEFINITION
Angles and proportions of a diamond:
Based on scientific formulas, a well-cut diamond will internally reflect
light from one mirror-like facet to another and disperse and reflect it
through the top of the stone. This results in a display of brilliance and
fire, thereby placing well-cut diamonds higher on the Diamond Quality Pyramid
than deep or shallow-cut diamonds. Diamonds that are cut too deep or too
shallow lose or leak light through the side or bottom, resulting in less
brilliance and ultimately, value.
Cut also refers to shape—round, square, pear, or heart, for example.
Since a round diamond is symmetrical and capable of reflecting nearly all
the light that enters, it is the most brilliant of all diamond shapes and
follows specific proportional guidelines. fancy shapes will have their
own guidelines to be considered well-cut.
Many people are confused about how diamonds are priced. The best explanation
is that asking for the price of a diamond is like asking for the price
of a house. A real estate agent can’t quote you a price for a house
without knowing its size, condition, location, etc. This is the same when
buying a diamond. A diamond’s beauty, rarity, and price depend on
the interplay of all the 4Cs—cut, clarity, carat, and color.
The 4Cs are used throughout the world to classify the rarity of diamonds.
Diamonds with the combination of the highest 4C ratings are more rare and,
consequently, more expensive. No one C is more important than another in
terms of beauty and it is important to note that each of the 4Cs will not
diminish in value over time.
Once you have established the 4C characteristics that are most important
to you, your 4AntwerpDiamonds.com expert can then begin to show you various
options with quoted prices.
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DIAMOND COLOR DEFINITION
A degree in which a diamond is colorless:
Diamonds range in color from icy winter whites to warm summer whites. Diamonds
are graded on a color scale established by the Gemological Institute of
America (GIA) which ranges from D (colorless) to Z.
Warmer colored diamonds (K-Z) are particularly desirable when set in
yellow gold. Icy winter whites (D-J) look stunning when set in white
gold or platinum.
Color differences are very subtle and it is very difficult to see the
difference between, say, an E and an F. Therefore, colors are graded
under controlled lighting conditions and are compared to a master set
for accuracy.
Truly colorless stones, graded D, E, and F are treasured for their rarity,
are highest on the Diamond Quality Pyramid. Color, however, ultimately
comes down to personal taste. Engagement ring color selection should
generally stay in the range of D through J.
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D-F
Colorless
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G-J
Near Colorless
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K-M
Slightly Tinted
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N-R
Very Light Yellow
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S-Z
Light Yellow -
Yellow
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Descriptions for the most popular diamond colors:
Color: D
A diamond of this color grade is highly prized, as a diamond with less
color has never been found. This grade of diamond is absolutely colorless.
Color: E
An E-color diamond is colorless and also highly prized. Only a trained
gemologist using special equipment can determine any color difference
between a D- and an E-color diamond.
Color: F
No color is visible to an untrained eye in an F-color diamond. As the
least expensive diamond color in the colorless range, F-color diamonds
display minimal color difference from D- or E-color diamonds and offer
a lower price. This is the best value for a colorless diamond.
Color: G
This diamond is nearly colorless. A diamond with G-color has an extremely
faint tint that is only noticeable to a trained gemologist. G-color diamonds
offer great values and make for beautiful jewelry, since they are less
expensive than the colorless grades, but appear to the eye to be colorless
when mounted.
Color: H
This diamond offers an exceptional balance of color and cost in the near-colorless
range. If you choose an H-color grade diamond, you can buy a larger diamond
for same the price as a higher color grade. The very slight tint is generally
not noticeable.
Color: I
This diamond, when cut to ideal proportions, produces a warm brilliancy
not found in the higher grade colors. I-color diamonds are less expensive
than other diamonds, so you can buy a larger diamond for the same price
as a higher color grade. Note: If this diamond has medium or strong blue
fluorescence, its slight tint will be partially masked, making the diamond
appear whiter to the eye. with a negligible visible difference from an
ideal-cut diamond, but at a lower price.
Color: J
This diamond, when cut to ideal proportions, produces a warm brilliancy
not found in the higher grade colors. As the least expensive diamonds
in the near-colorless range, J-color diamonds present the best value
in diamond color, so you can buy a larger diamond for for the price.
Note: If this diamond has medium or strong blue fluorescence, its slight
tint will be partially masked, making the diamond appear whiter to the
eye.
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DIAMOND CLARITY DEFINITION
The presence of inclusions in a diamond:
Inclusions are natural identifying characteristics such as minerals or
fractures, appearing while diamonds are formed in the earth. They may
look like tiny crystals, clouds or feathers. The fewer and smaller the
inclusions the higher the clarity grade.
To view inclusions, you must use a magnifying loupe. This tool allows
you to see a diamond at 10x its actual size so that inclusions are easier
to see. The position of inclusions can affect the value of a diamond.
There are very few flawless diamonds found in nature, thus these diamonds
are much more valuable.
Inclusions are ranked on a scale of perfection, known as clarity, which
was established by the Gemological Institute of America (GIA). The clarity
scale, ranging from F (Flawless) to Included (I), is based on the visibility
of inclusions at a magnification of 10x.
Some inclusions can be hidden by a mounting, thus having little effect
on the beauty of a diamond. An inclusion in the middle or top of a diamond
could impact the dispersion of light, sometimes making the diamond less
brilliant.
The greater a diamond's clarity, the more brilliant, valuable and rare
it is and the higher it is on the Diamond Quality Pyramid.
Internally Flawless - IF
Free from internal blemishes visible under 10x magnification. (small
external details tolerated)
Very very slightly included - VVS
Inclusions and/or external blemishes very difficult to locate under
10x magnification.
Very slightly included - VS
Inclusions and external blemishes which are difficult to locate under
10x magnification.
Slightly Included- SI
Inclusions and external blemishes easy to locate under 10x magnification.
Included - I
Medium or large inclusions on external blemishes which are obvious
to the naked eye under favorable lighting conditions.
POPULAR DIAMOND CLARITY GRADES
Clarity: Internally Flawless (IF)
This diamond has no internal identifying characteristics, even when
viewed under a microscope at extreme magnification. These diamonds
are not graded flawless usually because of very slight surface markings
or minor details in their polish. Diamonds of this grade of clarity
are extremely rare.
Clarity: Very, Very Slightly Included (VVS1)
This diamond has very few, very tiny inclusions. The inclusions in
this diamond are virtually unidentifiable even when viewed under
a microscope at 30x power magnification. Diamonds of this grade of
clarity are extremely rare.
Clarity: Very, Very Slightly Included (VVS2)
This diamond has very few, very tiny inclusions. The inclusions in
this diamond are virtually unidentifiable even when viewed under
a microscope at 30x power magnification. Diamonds of this grade of
clarity are extremely rare
.
Clarity: Very Slightly Included (VS1)
This diamond has few, very small inclusions. The inclusions are very
difficult to see under a 10x power magnification, and are almost
never visible to the unaided eye. VS1 grade diamonds present an excellent
value in clarity because they are typically free of visible blemishes,
and they are less expensive than higher clarity grades.
Clarity: Very Slightly Included (VS2)
This diamond has few, very small inclusions. The inclusions are very
difficult to see under a 10x power magnification, and are almost
never visible to the unaided eye. VS2 grade diamonds present an excellent
value in clarity because they are typically free of visible blemishes,
and they are less expensive than higher clarity grades.
Clarity: Slightly Included (SI1)
The inclusions in this diamond can be visible at 10x power magnification.
Inclusions in diamonds with SI grade clarity might be visible to
the unaided eye. SI1 grade diamonds are not as rare as VS1 and VS2
grade diamonds, so they are less expensive and present a great value.
Clarity: Slightly Included (SI2)
The inclusions in this diamond can be visible at 10x power magnification.
Inclusions in diamonds with SI grade clarity might be visible to
the unaided eye. SI2 grade diamonds are not as rare as SI1 and VS2
grade diamonds, so they are less expensive and present a great value.
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DIAMOND CARAT DEFINITION
Refers to the weight of a diamond:
Carat is often confused with size even though it is actually a measure
of weight. One carat is equivalent to 200 milligrams. One carat can
also be divided into 100 points. A .75 carat diamond is the same
as a 75-points or 3/4 carat diamond.
A 1 - carat diamond costs exactly twice the price of a half-carat
diamond, right? Wrong. Since larger diamonds are found less frequently
in nature, which places them at the rarest level of the Diamond Quality
Pyramid, a 1 - carat diamond will cost two times more than a 1/2
- carat diamond (assuming color, clarity and cut remain constant).
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DIAMOND CERTIFICATION
Company who certified the diamond:
When you receive your diamond you will also receive its certificate.
This is a quality analysis of your diamond and guarantee of the quality
and value of that diamond. Though the 4Cs are commonly used as guides
in diamond purchase, only experts in gemology can really evaluate
a diamond based on these 4 characteristics. In grading a diamond,
gemologists use highly sophisticated spectrometers and other high-tech
equipment. Independent gemological laboratories issue a document
containing the vital characteristics and the grading of the 4Cs.
A diamond certificate, also called a diamond grading report, diamond
dossier®, or diamond quality report, is a report created by a
gemologist, or gemologists, who have scrutinized the diamond and
placed it under a microscope to analyze its dimensions, clarity,
cut, color, finish, symmetry, and other characteristics.
Every loose diamond sold by this site has been analyzed and graded
by a major independent grading lab such as Gemological Institute
of America (GIA), American Gem Society Laboratories (AGSL) and the
European Gemological Laboratory (EGL). They are the most respected
laboratories in the diamond industry. These laboratories are known
for having the strictest, consistent, and unbiased systems for grading
diamonds. Diamonds that are accompanied by these grading reports
are the most highly valued in the industry, as their quality is considered
guaranteed.
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DIAMOND CARE
Care and cleaning your Diamond:
A solution of one part ammonia and six parts water can be used to
clean diamond jewelry at home or you can buy jewelry cleaner in almost
any super-market. Once a year, we suggest having your diamond cleaned
professionally and have the security of the setting checked to make
sure your diamond is secure. Always use a soft cloth to dry your
jewelry, so you never scratch your gold or platinum.
Diamonds are the hardest substance on earth, therefore we recommend
that you keep your sparkly diamond separate from the rest of your
jewelry. We also recommend that you use a jewelry box or soft pouch
to store you diamonds.
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DIAMOND GLOSSARY
Relevant diamond terms and definitions:
Abrasion: Damage to the culet or facet
edges usually caused by contact with other diamonds.
Age: The age of a diamond ranges between
1000 to 3,300 million years.
AGS: American Gem Society, Las Vegas,
USA
Beard: Feather-like inclusions located
on the girdle resulting from poor bruting.
Bezel: Angled surface located on the
crown of a stone between the girdle and table.
Bezel Facet: Four sided facets found
on the bezel of a brilliant cut.
Bow Tie: Term used to describe the
dark area located across a table sometimes found in fancy shapes
(aka 'Butterfly').
Brilliance: Intensity of the light
reflecting out of the stone through the crown (aka 'Dispersion',
'Fire').
Brilliant: Symmetrical cut with a round
girdle outline, featuring 56 facets.
Brilliant Cut: Collective name for
diamond cuts whose lower facets radiate from the center of the stone
towards the girdle, the most
common of which is the round cut.
Butterfly: Term used to describe the
dark area located across a table, sometimes found in fancy shapes
(see 'Bow Tie').
Cape (Color): Term used to describe
yellow diamonds found in the M to Z range of the color grading scale.
Carat: Standard weight unit for gemstones;
1 carat = .2 grams
Cavity: An opening or indentation on
the surface of a diamond (see 'Pit').
Certificate: Document provided by an
accredited laboratory stipulating the stone's weight , color, clarity,
proportions and finish grade.
Clarity: A stone's relative freedom
from inclusions and imperfections. Expressed in a fixed grading scale.
Cleavage / Gletz / Feather: A break or fracture in the stone which
may be internal or external. These usually occur along the crystal's
growth planes (see also 'Cleavage' 'Gletz', and 'Feather').
Cloud: A milky area in a stone made
up of a multitude of small inclusions. This phenomenon may be local
or spread throughout the stone.
Color: This may range from white to
brown and is defined by a standard nomenclature ('grading scale'),
ranging from D to Z.
Crown: The part of the stone located
above the girdle.
Crystal Inclusion: An impurity within a stone
with a geometric, crystal- like shape.
Culet: The small facet on the point
of the pavilion.
Cut: The proportions, make and finish
of a polished diamond or the actual shape of the stone.
D: The highest colour grade on the
international colour grading scale. Very white
.
Dark Centre: A dark area visible
through the table in a stone of sub-standard make, i.e. stone is
too deep.
Dark Inclusion: An impurity in the
stone which is dark in color (normally black)
.
Dead Stone: A stone so heavily included
that there is no brilliance.
Depth: The height of a diamond measured
from culet to table.
Diamond: A carbon based mineral created
under extreme pressure and temperature. Diamond is the hardest
of all known substances
and exists
in a variety of colours ranging from white to fancy colors.
Dispersion: Intensity of the light
reflected out of the stone through the crown (see 'Brilliance'
and 'Fire').
European Gemological Laboratory (EGLUSA): Grading Lab in New York
Emerald Cut: Rectangular or square
step cut with diagonally cut corners.
External Characteristics: Imperfections
located on the surface of a stone.
Extra Facet: Any facet added to the
stone which is in excess of the facets normally required to complete
the polishing. Usually
found
along the girdle to remove any imperfections.
Facet: Flat polished surface on a
polished stone.
Faceting: The process of polishing
facets onto a stone.
Fancy Color: A naturally colored
diamond with varying degrees of rarity. Yellow, Pink, Brown are
some examples. Colored diamonds
also come in color grades called Light Fancy, Fancy, Fancy Intense
and
Vivid Fancy.
Fancy Shape: Any other shape besides
the brilliant cut.
Feather: A break or fracture in the
stone which may be internal or external. These usually occur along
the crystal's growth planes
(see
also 'Cleavage' and 'Gletz').
Finish: The quality of the diamond's
polish.
Fire: Intensity of the light reflecting
out of the stone through the crown (see 'Brilliance' and 'Dispersion').
Fisheye: A diamond whose pavilion
is too shallow and, as a result, a circular reflection of the girdle
is seen through the table.
Flat Stone: A stone with a shallow
crown or pavilion.
Fluorescence: A visible light occasionally
emitted from diamonds when exposed to ultraviolet light, usually
blue in color. The visible
effects of fluorescence grades of faint, inert, negligible, and
medium, can only be detected by a trained gemologist. A fluorescence
grade
of strong or very strong can make a diamond with a near-colorless
grade look even whiter yet in some instances give the diamond a
slight hazy or oily appearance. Diamonds with a strong or very
strong fluorescence
are priced slightly lower than other diamonds.
Four C's: Carat, Cut, Color and Clarity:
the four factors determining the value of a diamond.
Gem / Gemstone: Mineral or organic material with sufficient beauty,
rarity and durability to be set into jewelry.
GIA: Gemological Institute of America,
Carlsbad, CA
Girdle: The edge located between
the pavilion and the crown which travels around the entire stone.
Girdles are usually faceted.
Grain: Weight unit equivalent to
0.25 carats. (i.e. 1.00 ct stone is a four-grainer)
Graining: Irregularities in the crystal
structure of a stone which show up as faint lines. These travel
throughout the stone and may
be internal or external.
Hardness: A stone's resistance to
wear and scratching measured on Mohs hardness scale. A diamond's
hardness is 10, which is the
hardest
on the scale.
Heart Shape (H.S): Modified brilliant cut with a heart-shaped girdle
outline, featuring 56 facets.
Hearts & Arrows: A stone polished
to ideal proportions with exceptional symmetry and polish which
shows eight heart shapes
(Pavilion) and
eight arrows (Crown) when observed through a special viewer.
HRD: Certification company Diamond
High Council.
IGI: Certification and Appraisal
company International Gemological Institute.
Imperfection: Blemish located within
the stone, occasionally reaching the exterior.
Included: Clarity grade, referring
to eye visible imperfections, existing in I1,I2,I3
Inclusion: Internal imperfections
that effect the clarity grade of a diamond.
Industrial Diamonds: Non-gem quality
diamonds used in drills and other tools.
Internal Reflection: The reflection
of a feature within a stone.
Kimberlite: Volcanic diamond-bearing
rock (also called blueground).
Laser Cut: Using a laser to fashion
the diamond's eventual shape, allowing cuts across the growth plains,
thus permitting odd shapes
such as letters, horse heads etc.
Laser Inscription: Using a laser
to engrave identifying text or numerals, most commonly found on
the girdle.
Leveridge Gauge: Tool used to measure
the precise dimensions of a mounted or un-mounted stone.
Lively Stone: A stone with good brilliance
and luster.
Loupe: Small magnifying glass used
in the diamond trade to examine diamonds. Magnification may vary,
but all diamonds are graded under
10X.
Loupe Clean: When viewed under magnification
10X, a stone is considered loupe clean if no imperfections are
seen.
Lower Girdle Facet: Triangular shaped
facets, located on the pavilion.
Lower Main Facet: Eight, four sided
facets meet at the center to form the culet (syn. 'Pavillion facet')
Make: The quality of the symmetry
and finish of a polished stone.
Marquise: Symmetrical boat-shaped,
brilliant cut with pointed ends.
Masterstones / Color Samples: A set
of polished stones which have been colour graded by an accredited
laboratory for the purpose
of color grading polished diamonds.
Measurements: The diameter, width,
and depth of a diamond in millimeters.
Microscope: Magnifying instrument
used to determine clarity in gemstones.
Mohs: Scale used to determine the
hardness of minerals. A diamond is the hardest at 10 and talc is
the softest at 1.
Natural: Original surface of the
rough stone left on the polished stone. This is usually found on
the girdle.
Nick: Small chip on a diamond usually
as a result of contact with other stones.
Open Table: An inclusion which breaks
the surface of the stone and shows a small pit.
Oval: Modified brilliant cut with
an oval shaped girdle outline.
P.C.: Abbreviation for "Per
Carat"
Parcel Paper: Folded sheets of paper
used to contain polished or rough diamonds.
Pavilion: The section of the diamond
found below the girdle.
Pavilion Facet: Eight, four sided
facets meet at the centre to form the culet (syn. 'Lower main facet')
Pear Shape (P.S): Asymmetrical cut
with one pointed and one rounded end with a pear-shaped girdle
outline, featuring 56-58 facets
.
Pinpoint Inclusion: Very small inclusion
which may be black or white in colour, yet is not distinguishable
as a crystal. When
clustered
together, they are called a group of pinpoints.
Pit: Tiny opening on the surface
of a polished stone (see 'Cavity').
Point: Weight unit. 1 point is 1/100
of a carat.
Pointer: Term used to describe polished
stones under a carat.
Polish: The degree of polish on a
finished stone. For the highest grade of polish, look for an ideal
(ID), excellent (EX), or very
good (VG) AGSL graded diamond, and an excellent (EX) or very good
(VG) GIA graded diamond. For the best balance of price and quality,
look for a GIA or AGSL polish grade of good (G). Avoid diamonds
with polish grades of fair (F) or poor (P), as the quality of their
polish
may affect the brilliance of the diamond.
Polishing Lines: Small, parallel
indentations left on facets during the polishing process.
Princess: Modified brilliant cut
with a square or rectangular girdle outline, featuring 57 facets.
Proportions: The relative symmetry
of angles and measurements of a polished diamond.
Quality: Term used to describe the
overall color, clarity and cut attributions of a stone.
Reflection: The bouncing back of
light when it strikes an external or internal facet on a polished
diamond
.Rough: (Stone
or Diamond) Diamond of industrial or gem quality before it undergoes
any manufacturing process.
Round Cut: Round brilliant cut.
Scratch: The damage to a polished stone
which appears as a faint white line, due to contact with other diamonds.
Star Facet: A triangular facet
located on the crown of a brilliant cut next to the table,
of which there are eight.
Symmetry: The accuracy with which
the diamond is polished to its perfect proportions. For the
highest grade of symmetry,
look for
an ideal (ID), excellent (EX), or very good (VG) AGSL graded
diamond, and an excellent (EX) or very good (VG) GIA graded
diamond. For
the best balance of price and quality, look for a GIA or AGSL
symmetry grade of good (G).
Synthetic Diamond: A non-natural
diamond which has been produced by man.
Table: Large facet in the center
of the crown on a polished diamond.
Thermal Conductivity: The ability
of a material to conduct heat. Diamonds have the highest conductivity
of any material.
Ultraviolet: Lower end of the
light spectrum which is invisible to the human eye and allows
fluorescence to be visible in a
diamond.
Upper Girdle Facet: Triangular
facets located on the lower part of the bezel, right above
the girdle.
Wavy Girdle: A girdle which has
been improperly polished and does not run evenly.
Weight: Diamond weight is measured
in carats, subdivided in grains and points.
Well Made: A well proportioned,
polished diamond with a good finish.
White: A term used to describe
the diamonds that are H color and up
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