Diamond Cut

Cut has a great impact on the diamonds appearance and comprises numerous aspects. Cut determines the fire and sparkling beauty of a diamond. It shouldn’t be shallow or deeper to achieve perfection of a diamond.

When it comes to diamonds the word cut does not only mean the shape of a diamond (round brilliant, princess, oval, cushion) but it also comprises the symmetry, polishing, angles and the proportions of each part of a diamond.

One shouldn’t underestimate the role of the cut. Being the major factor of diamond`s brilliance and fire, cut has the biggest impact on the beauty of a diamond. Only a perfectly cut diamond can properly reflect the light and return it through the top so that it produces sparkling effect. The angles should also be cut perfectly to refract the light and to optimize the reflection of light back to your eye.

Diamond Proportions

The diamond cutting is a very complicated work. As a price for the rough diamond is high, cutters take efforts to lose as little rough material as possible. If the cutter, neglecting proportions of the stone, opts only for weight, the diamond will be deprived of its perfect form and sparkling beauty to a great extent.

The typical brilliant cut diamond contains 58 facets (33 on the crown and 25 on the pavilion). It takes plenty of time for a good cutter to make all the facets symmetrical and harmonious.

Infringements of this rule cause improper light reflection.

One natural rough diamond can provide two well-proportioned stones: one large 1.00 carat diamond and one small 0.5 carat one. The same weight natural rough diamond can be cut into two poorly proportioned diamonds of approximately one carat each.

A perfectly cut diamond is considered to lose more of the rough material than that with deeper and shallow cuts.

The two crucial factors, affecting the diamond proportions are the depth percentage and the table percentage.

To calculate the diamond’s depth percentage we need to divide the depth of the diamond (from table to culet) by the width (average diameter) of the stone. The depth percentage for a well-cut round diamond ranges between 59-62.5%. If this number is higher, the stone looks deeper and if it is lower, the gem looks shallower. For instance, a diamond with a depth of 4.09 mm and the width of 6.75 mm equates to the percentage of 60.6%. Such diamond is considered to be perfectly cut one.

To find out the table percentage we need to divide the table width by the whole diamond’s width. A good gemstone possesses the table percentage between 53-59%. For example, a diamond with the table of 3.91 mm and width of 6.75 mm equates to a table percentage of 57%. If the number is lower, the table looks smaller.

If the diamond is perfectly round, the length and width measurements coincide. Very frequently, however, we deal with off-round shape. In this case, the diamond is considered to be well-cut, provided the length is larger than the width by less than 0.10 mm. For two-carat stones the deviation may come up to 0.12 mm.

It is very important to be attentive while buying a gemstone because the majority of diamonds on the market are poorly proportioned.