What Is a Brilliant-Cut Diamond? From Diamond to Brilliant

Short answer: A brilliant diamond is a diamond cut with the “brilliant” cut that returns the most light. Diamond is the name of the mineral; the brilliant is that mineral cut as a gem. It is made of pure carbon, it is the hardest known natural material, and because it bends light so strongly it sparkles differently from other stones. Its value is measured by carat, cut, colour and clarity, and it can form in nature or be grown in a laboratory.

Are a diamond and a brilliant the same thing?

Every brilliant is a diamond, but not every diamond is a brilliant. A rough diamond, whether it comes out of the ground or is grown in a laboratory, is a matte, irregular crystal. Craftspeople cut it so that it returns the most light; in Turkish, a diamond cut as a round brilliant is called “pırlanta”. In everyday speech, oval, pear and princess cut diamonds are often called brilliants too. More: diamond versus brilliant.

What makes a diamond a diamond

The high refractive index makes light that enters the stone reflect inside and come back out through the top. That is why a well-cut diamond gives white light, coloured flashes and sparkles that flicker as it moves. Diamond brilliance.

The brilliant cut: 57 facets

The classic round brilliant cut has 57 surfaces, or facets (58 counting the tiny flat at the bottom). The angles of these facets are calculated so that light comes back without escaping from the stone. The proportions of the modern brilliant cut were calculated in the early 20th century and have been used with small refinements ever since. Cut quality is the most important factor in how much a diamond sparkles. What is cut quality?

How is a diamond graded? The 4Cs

• Carat: The stone’s weight; 1 carat is 0.2 grams. What is a carat?
• Cut: Proportions, symmetry and polish.
• Colour: A scale from D (colourless) towards Z. What does G colour mean?
• Clarity: How visible the inner and outer marks are. The clarity scale.

We explain how to balance all four in the 4Cs of diamonds.

Natural and lab-grown diamonds

A natural diamond forms deep in the earth under very high pressure and temperature. A lab-grown diamond is the same crystal grown in a controlled environment: its chemistry, hardness and light are the same. The two cannot be told apart with the naked eye; the difference is origin, and it is written on the certificate. How do diamonds form? · What is a lab-grown diamond?

Which jewellery uses diamonds?

The best-known use is the solitaire ring, but diamonds are also used in wedding bands, eternity rings, five-stone rings, earrings, necklaces and bracelets. You can see real photos of pieces made in our workshop in the model gallery, and you can design your own solitaire.

Frequently asked questions