The polished diamonds means to the diamonds that passed the manufacture process which include polish, cleaning and design . After the manufacture process that you can learn more about it under "The Industry" channel, the designated polished diamond is ready to be added to a desirable match jewelry. The value of the polished diamond fixed according to 4 criterions which called " The 4'cs" : Carat , Cut , Color , Clarity.

There is another criterion which developed recently, and we mean the flouresance of the diamond. The flouresance scale was created parallel to the use with an ultra-violet light specially in the United stats. the price of a flouresance diamond is devalued dramatically between 10 to 30 percent below the fixed price.

A carat is the term used for the measurement of a diamond's weight. It is equal to 200 milligrams, or 0.2 grams, and there are 142 carats to an ounce. (This is a totally different term from the "karat" weight of gold, which is actually a measurement of purity rather than weight).

For jewelry purposes, carats are further divided into points, a one-carat stone equaling 100 points. Therefore, a half-carat stone may be referred to as a "50-pointer," a quarter carat, "25-points," etc. The smaller stones used in pave or channel settings are sometimes called melee. In certificates, appraisals and receipts, however, the weight of your diamond should be written in carats, rounded to 1/100ths, such as .25 carats; .50 carats, 1.20 carats, etc.

Another fact that's important to understand is that prices of diamonds rise proportionately with the size of the stone. Because large diamonds are rare, they generally have a greater value per carat.

Cut is the most misunderstood of the 4 Cs. It is often wrongly thought of as the shape of the stone. This confusion exists because, of course, the raw material must be cut into a shape, and the confusion increases because shapes of diamonds are given names like Round Brilliant Cut, Oval Cut, Emerald Cut, and so forth.

Refers to the degree to 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 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 compared to a master set for accuracy.

Truly colorless stones, graded D, treasured for their rarity, are highest on the Diamond Quality Pyramid. Color, however, ultimately comes down to personal taste. We can show you a variety of color grades next to one another to help you determine your color preference.

The clarity of a diamond refers to how clear, or "clean" the diamond is. The more "clean" the diamond, the higher the price. Most diamonds have "imperfections" in them. The clarity scale is a measure of the severity of those imperfections or "inclusions" as it is known in the trade.

* Outside of the GIA Diamond clarity scale is a grade you may have seen called SI3. The Rap Sheet, which is a Trade Publication, honors the SI3 grade which is given out by EGL, the European Gemological Laboratory. It is described as a split between the SI2 and I1 clarity grade.