Jewlery Design1
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Challenging the notion of "perceived value" Todd Reed sets raw, unpolished, diamonds next to their polished and faceted counterparts, To honor their "perfect geometry," Todd will feature larger rough diamonds in their natural octahedral cubic, or macle shapes; "I want it to look like it was just dug out of the dirt." Todd's studio is in Boulder, Colorado.
Modern Diamond Cutting
|One of the hardest substances on earth, only a diamond is hard enough to cut other diamonds. Polishing and mounting add brilliance to the stone and increase it's value. Diamond cutting can be traced back to the late Middle Ages. Prior to this time, diamonds were used in their natural octahedral state. The first improvements on nature's design involved a polishing of the crystal faces, which was called the "Point Cut". As further refinement progressed, one half of the crystal would be cut off, creating the "Table Cut". At the time, diamonds were valued primarily for their luster and hardness. Table Cut diamonds appeared black to the eye. The Modern Round Brilliant cut (below) is the culmination of several hundred years of experimentation and development
Diamond Clarity
|When we speak of a diamond's clarity, we are referring to the presence of identifying characteristics on (blemishes) and within (inclusions) the stone.
If you think about the incredible amount of pressure it takes to create a diamond and the fact that natural diamonds are not grown in a sterile laboratory, it's no surprise that most diamonds have flaws.
Basically there are two types of flaws: inclusions and blemishes. Inclusions refer to internal flaws and blemishes refer to surface flaws. However, in the diamond grades listed below, you'll note that none of the grades include the term "blemish" -- for the purposes of grading diamonds, all flaws are called "inclusions."
Inclusions include flaws such as air bubbles, cracks, and non-diamond minerals found in the diamond. Blemishes include scratches, pits, and chips. Some blemishes occur during the cutting processes (most often at the girdle). Diamonds with no or few inclusions and blemishes are more highly valued than those with less clarity because they are rarer.
How are diamonds graded for clarity? Diamonds are graded for clarity under 10x loupe magnification. Grades range from Flawless (diamonds which are completely free of blemishes and inclusions), to Included 3 (diamonds which possess large, heavy blemishes and inclusions that are visible to the naked eye).
F Flawless: No internal or external flaws. Extremely rare.
IF Internally Flawless: no internal flaws, but some surface flaws. Very rare.
VVS1-VVS2 Very Very Slightly Included (two grades). Minute inclusions very difficult to detect under 10x magnification by a trained gemologist.
VS1-VS2 Very Slightly Included (two grades). Minute inclusions seen only with difficulty under 10x magnification.
SI1-SI2 Slightly Included (two grades). Minute inclusions more easily detected under 10x magnification.
REMEMBER: For grades F through SI, a diamond's clarity grade has an impact on the diamond's value, not on the unmagnified diamond's appearance.
I1-I2-I3 Included (three grades). Inclusions visible under 10x magnification AS WELL AS to the human eye. We do not recommend buying diamonds in any of these grades.
Diamond Cut
|First, don't confuse diamond "cut" with "shape." Shape refers to the general outward appearance of the diamond, (such as round, emerald, or pear). When a diamond jeweler (or a diamond certificate) says "cut," that's a reference to the diamond's reflective qualities, not the shape (or at least it should be, we have found that even some "jewelers" don't appear to know the difference between "cut" and "shape").
The quality of the "cut" does make a difference in how a diamond looks.
Diamond cut is perhaps the most important of the four Cs, so it is important to understand how this quality affects the properties and values of a diamond. A good cut gives a diamond its brilliance, which is that brightness that seems to come from the very heart of a diamond. The angles and finish of any diamond are what determine its ability to handle light, which leads to brilliance.
(See Diamond Anatomy for an explanation of the terms used in the next paragraphs.)
As shown in the images below, when a diamond is well-cut, light enters through the table and travels to the pavilion where it reflects from one side to the other before reflecting back out of the diamond through the table and to the observer's eye. This light is the brilliance we mentioned, and it's this flashing, fiery effect that makes diamonds so mesmerizing.
In a poorly cut diamond, the light that enters through the table reaches the facets and then 'leaks' out from the sides or bottom of the diamond rather than reflecting back to the eye. Less light reflected back to the eye means less brilliance.
Good Proportions are Key
Rough Diamond Grading Program
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DAY ONE
a. Explanation on sawing techniques and how it relates to rough octahedral diamonds.
b. Explanation on bruting and how it affects the rough diamond.
c. The procedure of cutting and polishing in relation to facet placement.
d. How the diamond cutting wheel is used and its affect on polishing.
e. The use of the star gauge and butterfly gauge.
f. Facet placement for rough diamonds and common terms used among diamond cutters.
g. Examining rough octahedrons and misshapen crystals.
h. Identifying trigons and other surface markings.
i. Differentiating between 2 point, 3 point and 4 point grain structures.
j. Expected weight retention on octahedrons and misshapen crystals.
k. Proportion percentages and expected angles for light reflection and the resulting fire and brilliance that can be expected from one crystal in respect to another.
The Rough diamond grading student will be able to observe first hand diamond manufacturing techniques performed by the Institute in house diamond cutters. This will demonstrate visually to the student the manipulation and fashioning of rough diamonds.
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