Carat (Ct)
The international unit of weight used for measuring diamonds and gemstones. 1 carat is equal to 200 milligrams, or 0.2 grams.
Polish
The overall condition of a finished diamond's faceted surfaces, including how smoothly the facets have been polished, whether any marks are visible from the polishing wheel, and how defined the edges of each facet are. Polish marks are almost always invisible to the unaided eye, but good polish is essential for maximum light performance.
Symmetry
The precision and alignment of a diamond's facets and the resulting effects on its brilliance.
Table
Usually the largest facet on a diamond, located on the top. The size of the table can have a considerable effect on the diamond's light performance or brilliance.
Length-to-width ratio
Length (L) divided by Width (W) is the Length-to-Width ratio. This conveys how relatively square or rectangular a fancy-shaped diamond appears when viewed from the top.
Ideal Length-to-Width Ratios
Asscher: 1 to 1.05
Cushion: 1 to 1.05 (square); >1.15 (rectangle)
Emerald: 1.3 to 1.4
Heart: 0.90 to 1.10
Marquise: 1.75 to 2.25
Oval: 1.33 to 1.66
Pear: 1.45 to 1.75
Princess: 1 to 1.05
Radiant: 1 to 1.05 (square); >1.10 (rectangle)
Fluorescence
A measure of the visible light some diamonds emit when exposed to ultraviolet (UV) rays. Diamonds with a strong or very strong fluorescence are a better value because the market prices them slightly lower. It is quite rare for fluorescence to have any visual impact on a diamond's appearance, and it does not compromise the gem's structural integrity in any way.
Cut Grade
A diamond's cut unleashes its light. Diamonds are renowned for their ability to transmit light and sparkle so intensely. We often think of a diamond's cut as shape (round, emerald, pear), but a diamond's cut grade is really about how well a diamond's facets interact with light.
Specialty Cut
- Brilliant
Brilliant:This technique creates triangular-shaped facets that face outwards from the center of the diamond. Most often the term is used to refer to round brilliant cuts, the most popular cut.
- Rose
Rose: An antique style cut with trangular facets coming to a point (no table) and a flat bottom (no pavilion).
- Step
Step: A cut with rows of long, rectangular facets resembling a staircase.
- European
European: Dating back to the 1800s, this cut possesses a circular girdle with a high crown, small table, and a large, flat culet. With 58 facets, it is the predecessor of today’s modern round brilliant cut.
- Old Miner
Old Miner: A cut dating back to the Victorian era that features a squarish girdle with gently rounded corners. Old mine cut diamonds have a high crown, a small table, and a large, flat culet.
- Single
Single: A round cut with only 17 or 18 facets, as opposed to the brilliant's 57 or 58 facets, and is common for "melee" diamonds.
- Flat
Flat: An unfaceted slice, disc, or similar shape.
- Grooved
Grooved: Certain shapes, particularly the princess cut, can be grooved on the edges to allow them to be "invisibly" set together (without prongs or metal in between).
Brilliant: This technique creates triangular-shaped facets that face outwards from the center of the diamond. Most often the term is used to refer to round brilliant cuts, the most popular cut.
Certificate
A diamond certificate, also known as a diamond report, is issued by an accredited independent gemological laboratory. In addition to the diamond's carat weight and measurements, a certificate includes grades for the diamond's cut, color and clarity.
Price
The total price of the stone found by multiplying the price per carat by the total carat weight.
Length
The measure of the longest side of the stone in millimeters.
Width
The widest point along the short side, in millimeters.
Color
- D
D color: Highest, absolutely "colorless" grade, appreciated best set in platinum or white gold. Exceptionally rare.
- E
E color: A "colorless" grade appreciated best set in platinum or white gold. Traces of color difficult for even trained eye to detect.
- F
F color: A "colorless" grade appreciated best set in platinum or white gold. Faint color detectable by a trained gemologist.
- G
G color: The highest "near-colorless" grade. Color may be detectable when compared to much higher "colorless" grades. Excellent value.
- H
H color: A "near-colorless" grade, color is only noticeable when compared to much higher color grades. Excellent value.
- I
I color: The last of the "near-colorless" grades, color may be only slightly detectable upon close examination. Exceptional value.
- J
J color: Color may be slightly detectable to the unaided eye, particularly in fancy shapes or diamonds over 1-carat.
- K-O
K-O color: Color is visibly subtle to distracting.
- P-Z
P-Z color: Color is visibly subtle to distracting.
D color: Highest, absolutely "colorless" grade, appreciated best set in platinum or white gold. Exceptionally rare.
Depth percentage
The height of a diamond, measured from the culet to the table, divided by its average girdle diameter. One of the basic proportions that contributes to a diamond's appearance, brilliance and fire.
Eyeclean
A description of whether or not inclusions can be seen with the naked eye, expressed as 100% eyeclean, 90% eyeclean, or not eyeclean. 100% eyeclean means that inclusion(s) cannot be seen with the naked eye even after they have been located with a loupe. 90% eyeclean means the inclusion(s) are generally not seen by the naked eye and can be seen only after first locating them under a loupe.
Hearts and Arrows
When viewed from the top or bottom, the diamond appears to have shapes resembling "hearts" and "arrows" radiating from the center, sometimes referred to as the "Cupid Effect". It is found in less than 1% of the world's diamonds as the phenomenon only occurs in round brilliant cuts with perfect optical symmetry.
Table White Inclusion
A white inclusion can be seen on the table when magnified with a 10x loupe. This does not describe the magnitude of the inclusion and can be a feather, pinpoint, crystal, etc.
Table Black Inclusion
A black inclusion can be seen on the table when magnified with a 10x loupe. This does not describe the magnitude of the inclusion and can be a feather, pinpoint, crystal, etc.
Side Black Inclusion
A black inclusion can be seen on the side of the stone when magnified with a 10x loupe. This does not describe the magnitude of the inclusion and can be a feather, pinpoint, crystal, etc.
Side White Inclusion
A white inclusion can be seen on the side of the stone when magnified with a 10x loupe. This does not describe the magnitude of the inclusion and can be a feather, pinpoint, crystal, etc.
SKU
This is a unique identifier we assign to our products to help you keep track of your favorite picks.
Lab Key To Sym
The lab key to symbols for the types of inclusions shown in the stone's lab plotting diagram such as feather, cloud, cavity, pinpoint, etc. These are listed from highest to lowest impact on the stone's clarity.
Stone Description
AGI's final take on the stone. AGI graders have gone the extra mile to thoroughly grade every diamond to give a professional opinion on the overall aesthetics of the stone including brilliance, bowties, cut quality, and face up coloring.
Stone Inclusion
AGI graders have carefully inspected each diamond to provide a professional description of the nature and magnitude of the stone's inclusions.
Lab Fluorescence Color
The color that the diamond fluoresces when exposed to UV radiation. A large majority of diamonds will fluoresce blue, but can also be yellow, white, green, or even pink.
Lab Inscription
A lab will sometimes incribe the diamond's certificate number along the girdle as a security feature to identify the stone, and may also indicate certain features, like hearts and arrows, or treatments like HPHT. Individuals may also choose to inscribe personalized messages on their stone. These inscriptions can be viewed with a microscope.
Lab Treatment
Diamonds are tested/examined for laser drilling, glass filling, surface coating, High Pressure/High Temperature (HPHT) processing, and irradiation. Surface coated or fracture-filled stones are not issued GIA grading reports.
HPHT: High pressure/high temperature treatment has been used to lighten, alter, or remove color from the stone.
Laser Drilled: A laser has been used to bore a very small hole into the diamond's interior to burn away a dark inclusion.
Irradiation: A genuine diamond has been exposed to high radiation to permanently shift its color to blue, green, pink, etc.
Lab Girdle %
The girdle's percentage of total height. An ideally cut diamond will have a girdle percentage of 2.2%.
Lab Crown Height
The height of the crown from table to girdle, expressed as a percentage of the diamond's diameter. An ideally cut diamond will have a crown height of 14.2-16.2%.
Lab Pavilion Depth
The depth of the pavilion from girdle to culet, expressed as a percentage of the diamond's diameter. An ideally cut diamond will have a pavilion depth of 42.2-43.8%.
Lab Girdle Condition
An evaluation of the girdle of the stone for polishing, bruting (on round stones), or faceting (shown above).
Lab Culet Condition
A evaluation of whether or not the culet is nicked, chipped, or open.
Lab Crown Height
The height of the crown from table to girdle, expressed as a percentage of the diamond's diameter. An ideally cut diamond will have a crown height of 14.2-16.2%.
Lab Crown Angle
The angle of elevation of the crown from the horizontal (girdle). An ideally cut diamond has a crown angle of 33.7-35.8 degrees.
Lab Pavilion Angle
The angle of the pavilion facets with respect to the girdle. An ideally cut diamond has a pavilion angle of 40.6- 41 degrees.
Lab Report Issue Date
The date the stone was evaluated by the lab.
Price Per Carat
A common guideline used to evaluate a diamond's price. The price per carat of a diamond is affected by many factors including color, clarity, and size. Larger carat weight diamonds may have a higher price per carat because of their relative rarity compared to smaller size stones.
Culet
The facet or point at the bottom of a diamond pavilion. In preferred diamond cut grades, culets are generally undetectable to the unaided eye and graded none to small. Medium to large culets may have an impact on light performance.
Girdle Max
The thickest section on the girdle, the widest point of the diamond at the edge of the crown. Medium thickness is preferred, as a thin girdle is often fragile and a thick girdle adds unnecessary weight to the stone.
Girdle Min
The thinnest section on the girdle, the widest point of the diamond at the edge of the crown. Medium thickness is preferred, as a thin girdle is often fragile and a thick girdle adds unnecessary weight to the stone.
Measurements
The stone's length, width, and depth, respectively, measured in millimeters.
Weight
The weight in carats of the stone, measured to the nearest hundreth of a carat. One carat is equivalent to 0.2 grams.
Clarity
- IF
Flawless: No internal or external characteristics. Internally Flawless: May have external blemishes only. Both extremely rare.
- VVS1
VVS1: Very, very slightly included. Characteristics miniscule and difficult to see under 10x magnification, even to a trained eye.
- VVS2
VVS2: Very, very slightly included. Characteristics miniscule and difficult to see under 10x magnification, even to a trained eye.
- VS1
VS1: Very slightly included. Minor inclusions ranging from difficult (VS1) to somewhat easy (VS2) to see at 10x magnification.
- VS2
VS2: Very slightly included. Minor inclusions ranging from difficult (VS1) to somewhat easy (VS2) to see at 10x magnification.
- SI1
SI1: Slightly included. Inclusions noticeable at 10x. Best value if eye-clean. SI2 inclusions may be detectable to a keen unaided eye
- SI2
SI2: Slightly included. Inclusions noticeable at 10x. Best value if eye-clean. SI2 inclusions may be detectable to a keen unaided eye
- SI3
SI3: Slightly included. Inclusions noticeable at 10x. Best value if eye-clean. SI2 inclusions may be detectable to a keen unaided eye
- I1
I1: Included. Diamonds may have minor eye-visible inclusions. GIA offers a limited selection of jewelry with I1 clarity diamonds.
- I2
I2: Included. Will likely have more obvious or distracting inclusions. GIA does not carry I2-3 clarity diamonds.
- I3
I3: Included. Will likely have more obvious or distracting inclusions. GIA does not carry I2-3 clarity diamonds.
- I4
I4: Included. Will likely have more obvious or distracting inclusions. GIA does not carry I2-3 clarity diamonds.
Flawless:No internal or external characteristics. Internally Flawless: May have external blemishes only. Both extremely rare.
Availability
The number of stones available in this listing.
Clarity
- IF
Flawless: No internal or external characteristics. Internally Flawless: May have external blemishes only. Both extremely rare.
- VVS1
VVS1: Very, very slightly included. Characteristics miniscule and difficult to see under 10x magnification, even to a trained eye.
- VVS2
VVS2: Very, very slightly included. Characteristics miniscule and difficult to see under 10x magnification, even to a trained eye.
- VS1
VS1: Very slightly included. Minor inclusions ranging from difficult (VS1) to somewhat easy (VS2) to see at 10x magnification.
- VS2
VS2: Very slightly included. Minor inclusions ranging from difficult (VS1) to somewhat easy (VS2) to see at 10x magnification.
- SI1
SI1: Slightly included. Inclusions noticeable at 10x. Best value if eye-clean. SI2 inclusions may be detectable to a keen unaided eye
- SI2
SI2: Slightly included. Inclusions noticeable at 10x. Best value if eye-clean. SI2 inclusions may be detectable to a keen unaided eye
- SI3
SI3: Slightly included. Inclusions noticeable at 10x. Best value if eye-clean. SI2 inclusions may be detectable to a keen unaided eye
- I1
I1: Included. Diamonds may have minor eye-visible inclusions. GIA offers a limited selection of jewelry with I1 clarity diamonds.
- I2
I2: Included. Will likely have more obvious or distracting inclusions. GIA does not carry I2-3 clarity diamonds.
- I3
I3: Included. Will likely have more obvious or distracting inclusions. GIA does not carry I2-3 clarity diamonds.
- I4
I4: Included. Will likely have more obvious or distracting inclusions. GIA does not carry I2-3 clarity diamonds.
Flawless:No internal or external characteristics. Internally Flawless: May have external blemishes only. Both extremely rare.
Brown diamonds are graded on a tone and saturation scale from light champagne (C1-C2) to Cognac (C7).
