The Cut
Brilliance is a decision, not an accident.
Color and clarity are graded by nature. Cut is the one variable a human controls — and the one that decides whether a stone comes alive.
A short history
The round brilliant is a math problem, solved in 1919.
Marcel Tolkowsky, a young engineer from a family of diamond cutters, calculated proportions for returning light through the crown of a round stone. Modern cutters work from later grading systems and stone-specific decisions; a production maison should describe its actual method and evidence.
Facet geometry
Fifty-seven facets, each placed to a fraction of a degree.
A standard round brilliant carries 33 facets on the crown (including the table) and 24 on the pavilion below the girdle — 57 in total, sometimes 58 with a culet facet. Cut a fraction too deep or too shallow and light leaks out the bottom instead of bouncing back to your eye.
Weight vs. light
A heavier stone is not always a brighter one.
Carat retention can compete with face-up appearance when a stone is cut too deep. A responsible product page should publish the verified proportions and grading report so buyers can assess the trade-off.
Fire, in motion
One ray in. Three colors out.
White light enters the crown, reflects internally off two pavilion facets, and exits split into color — the same dispersion a prism shows, compressed into a single stone.