Types of Rough diamond sorting: After being found in a diamond mine, it is classified into three types,
1. Primary sorting – At Mines.
2. Secondary sorting or commercial sorting – At CSO / DTC and trading offices.
3. Manufacturer sorting (Market sorting or Third stage of sorting) – At Manufacturing offices Different stages of Assortment
-Different stages of Assortment
1. Primary Diamond sorting – At Mines.
This is the primary classification after diamonds are found in alkali. Here the diamond is cleaned with acid!
And are classified into 3 groups.
1. Gem quality diamonds,
2. Near Gem-quality diamonds,
3. Boart or crushing – boart.
All Diamonds Come From Mines:- The result would be like this,
1-GEM QUALITY DIAMONDS (20%).
2-INDUSTRIAL QUALITY DIAMONDS (80%).
-NEAR GEM QUALITY DIAMONDS (TOP INDUSTRIAL QUALITY40% to 60%)
-REST ALL (BOART OR CRUSHING – BOART)
According to the demand of the diamond market gem-quality diamonds also come for sale in the market.
India is the biggest buyer of “near gem-quality diamonds” here is the changing quality of diamonds by processing by skilled artisans.
There would be more than 5,000 possible rough diamond classifications.
2. Secondary sorting or commercial sorting – At CSO / DTC and trading offices.
Secondary diamond sorting or commercial diamond sorting is similar to the quality diamonds classified in sizes and smalls. There are diamonds more than 2 carats in size and diamonds below 2 carats in small. In addition, white, yellow, and brown colors are separated.
Sizes are classified into –
Stones: Unbroken crystal of less formation.
Shapes: Unbroken crystals of regularity.
Cleavages: Irregularly shaped diamonds or broken diamonds.
Diamond sorting in Smalls: is classified as follows:
Also called sawables, they are divided into 4 Categories:
Stones: Same as larger stones and shapes.
Chips: Same as larger cleavages.
macle: Twinned crystals of rough triangular shapes.
Flats: Crystals of irregular shape with flat parallel sides like a piece of broken glass.
Color sorting
White
– Exceptional white
– Medium white
-Dull white
Yellow
– Light yellow Medium yellow
– Darker yellow
brown
– Light brown
– Medium brown
– Darker brown
3. Market diamond sorting or the Third stage of diamond sorting
We know that all diamonds in DTC are classified commercially but in more space. For there are mixes of all types of diamonds, which have to be reclassified as per the requirement for manufacturing.
such as,
Clarity-wise sorting: Here diamonds are classified according to internal and external defects.
Color-wise sorting: Here it is classified by color. white, yellow, brown, fancy, and occur.
Shape-wise sorting: Here diamonds are classified according to their shape. octahedron, dodecahedron, cube, and triangle.
