imperial minerals and petrochemicals

Diamond Shapes

Diamonds come in a variety of shapes. Do not confuse cut with shape, cut is what determines how well-cut your diamond is, where as diamond shape is the shape it was cut into.

Round Brilliant - Do not confuse with round. The round brilliant is the modern version of the round which has been refined for maximum shine. The round brilliant is by far the most popular and has the best angles for which to shine maximum brilliance.

Oval - Not as popular for solitaires, but very popular for three stone anniversary rings, with two matching diamonds on the sides.

Princess - A square cut diamond that has refractive properties almost near round brilliant. The princess is the preferred square cut shape over radiant

Emerald - A more traditional shape, the emerald is not as popular as it used as it once was, but has an old world elegance to it.

Radiant - Popular before the princess shape was around, the radiant has more facets than a princess, but has the corners trimmed like the emerald shape. This shape is not widely popular.

Heart - Hard to find due to low demand, but some people prefer a heart shape diamond for sentimental purposes.

Marquise - Like the emerald, the marquise is a traditional shape. This is probably the fourth most popular shape behind the round, princess and oval.

Pear - Mostly used in pendants, the pear shape diamond is shaped in a tear drop shape and has fairly good proportions to refract light well.

Diamond Enhancements

There are a variety of diamond enhancements or treatments a diamond can undergo that can significantly alter the price of the diamond when compared to a natural diamond. The FTC requires all diamond merchants to disclose all diamond enhancements and treatments to their customers. Failure to do so can result in fraudulent charges and lawsuits against the diamond dealer. When buying a diamond, it is recommended to simply ask for a non-treated or enhanced diamond and have the merchant clearly indicate on the invoice somewhere that the diamond is in fact, not treated and 100% natural mined from the earth. Listed below are some treatments that are done with gemstones.

Bleaching: The use of chemicals or other agents to lighten or remove a gemstone's color to achieve a brighter/whiter diamond.

Gamma/Electron Irradiation: The use of gamma and/or electron bombardment to alter a gemstone's color; may be followed by a heating process. Heating: The use of heat in a high temperature sintering furnace to effect desired alteration of color, clarity, and/or phenomena.

Infilling/Fracture Filling: The intentional filling of surface breaking cavities or fractures usually with glass, plastic, opticon with hardeners and/or other hardened foreign substances to improve durability, appearance and/or add weight. The foriegn material will have a different index of refraction than diamond, and a trained gemologist can see the light bending within the stone.

Lasering: A laser is used to penetrate a diamond and remove certain black inclusions. Chemicals are then used to further reach and alter inclusions in diamonds, like Kingstone Oil.

Oiling/Resin Infusion: The intentional filling of surface cavities of a colorless oil, wax, natural resin, or unhardened man-made material into fissured transparent/translucent gemstones to improve appearance. (i.e., oil, man-made resin, paraffin, etc.)

Irradiation: The use of neutron bombardment, with the combination of any other bombardment and/or heat treatment to alter a gemstone's color.

Fancy Colored Diamonds

Some of the most sort after diamonds of today are the fancy colors such as Pink, Blue, Yellow, Green, Champagne & Fancy Cognac to name but a few. These fancy color diamonds come in varying depth of colour ranging from intense to very very light. As a rle the more intense the colour the higher the valued.

Ideal Cut Diamonds

So what is Ideal Cut? Everyone has their own opinion on what Ideal is. Some people prefer a diamond to have a somewhat larger table, say around 60%, so the diamond "looks" bigger, some want the Tolkowsky Ideal cut, as calculated in the early 20th century by mathematician Markov Tolkowsky. The diagram below describes the Class 1 and 2 grades of GIA. They are the largest body in the world for diamond grading, and we use their classifications to grade our diamonds. Class 1 is Ideal. Class 2 is Very Fine, Class 3 is Fair, and Class 4 is Poor. We do not sell Class 3 or 4 diamonds. All diamonds we sell that are 0.50ct or larger on this website fall into the GIA's definition of "Ideal - Very Fine" Class, and are as follows:

Please keep in mind that diamonds other than round brilliant do not always have their cuts measured in such detail because they are classified as "fancy cut" diamonds and have very loose tolerances. For more information regarding our "fancy cut" diamond specifications, please contact us.

When buying a diamond, especially a round brilliant cut diamond, it is always best to have a complete analysis of cut. This will tell you all the specifications of the diamond's cut such as table percentage, depth percentage, etc., usually obtained from a scope (or megascope). Ask your jeweler for this report on cut if you are making a large diamond purchase.

Please visit our fancy shape diamond specifications page for other shapes besides round brilliant.

Fancy Cut Ideal Specifications

Princess Cut Diamonds

KEY FACTORS	Class 1 Cut Premium	Class 2 Cut Fine Trade	Class 3 Cut Average	Class 4 Cut Below Avrg
Table Size	60%-71% of diameter	58%-77%	53%-85%	Below 53% Above 85%
Depth	64%-75% of diameter	58%-80%	56%-84%	Below 56% Above 84%
Crown Height %	8.5%-11%	6.0%-13%	4.0%-17.5%	Below 4.0% Above 17.5%
Girdle Thickness	thin-med or med.-thick	thin-thick	very thin - very thick	extra thin - extra thick
Polish & Symmetry	good - excellent	fair -good	fair-good	poor to fair

Pear, Marquise, Heart, and Oval Cut Diamonds

KEY FACTORS	Class 1. Premium Cut	Class 2. Fine Trade Cut	Class 3. Average Cut	Class 4. Below Average
Table Size	54%-61.5% of diameter	52%-64%	50%-70%	Below 50% Above 70%
Depth	59%-63% of diameter	58%-65.4%	46%-71%	Below 46% Above 71%
Crown Height %	12.5%-15%	11.1%-16.5%	8.7%-18.4%	Below 8.7% Above 18.4%
Girdle Thickness	thin-med. or med.-thick	thin-thick	very thin to very thick	extra thin to extra thick
Polish & Symmetry	good to excellent	good to excellent	good to fair	fair to poor
Length: Width Ratios	Class 1 & 2 Pr. 1.5-1.75 M.1.75-2.25	Class 1 & 2 Ht..98-1.02 O.1.33-1.66	Class 3 & 4 Pr.1.26-1.99 Mr.1.51-2.49	Class 3 & 4 Ht.0.91-1.24 Ov.1.26-1.74

Emerald and Radiant Cut Diamonds

KEY FACTORS	Class 1. Premium Cut	Class 2. Fine Trade Cut	Class 3. Average Cut	Class 4. Below Average
Table Size	60%-64.1% of diameter	58%-69%	53%-76%	Below 53% Above 76%
Depth	60%-65% of diameter	58%-69%	56%-78%	Below 56% Above 78%
Crown Height %	11.9%-15%	11.1-16.2%	8.5%-18.5%	Below 8.5% Above 18.5%
Girdle Thickness	thin-med or med.-thick	thin-thick	very thin to very thick	extra thin to extra thick
Polish & Symmetry	good - excellent	fair-good	fair-good	poor to fair
Length-Width Ratios	Emerald Cut: 1.26-1.99