The Diamond Certification Laboratory of Australia (DCLA)
Buy and sell diamonds with the help of the experts
Degree to which a diamond transmits light, directly relevant to the cloudiness or haziness of the actual diamond material, and the quality of the crystal. Click here to learn more about transparency and the DCLA Transparency Grading System.
Measure of brittleness, or resistance to fracture and breaking. Diamond has very good durability, but due to its directional hardness diamonds have certain planes of weakness along which they can split or break. Toughness and hardness together determine the durability of diamond.
Degree or depth of colour in terms of lightness or darkness. The tone of a coloured diamond can range from very pale to very dark; it is the degree to which the colour of a diamond approaches white on the pale end, and black on the dark end.
Diamond cut or shaped into a triangle with one corner cut off, and rows or steps of elongated facets running parallel to the girdle on both the crown and the pavilion. It is a modified version of a standard baguette cut.
Measure of the table width expressed as a percentage of the diameter. Table size is a proportion important to the balance between brilliance and dispersion.
Man-made versions of the diamonds found in the earth. Synthetic diamonds have the same chemical structure and properties as natural diamonds, but are created in a laboratory in only a few days, instead of in the earth over billions of years – they sell at a much lower price. Click here to learn more about synthetic diamonds.
Degree and regularity in shape and placement of facets, how well they align and relate to each other. Symmetry is very important to the life in a diamond, especially the brilliance; it affects how light is reflected and refracted in a diamond. Symmetrical round brilliant cut diamonds often display hearts & arrows.
Triangle shaped facets on a round brilliant cut diamond surrounding the table facet. When viewed as a whole, they resemble an 8-point star.