What Is an Antique Cushion Cut?
Genuine old mine cuts typically run 10-30% below modern cushions of equal weight, but exceptional or documented stones can erase that discount.
The antique cushion — the “old mine cut” and its descendants — is a diamond cut for candlelight, and it behaves unlike anything graded into today’s brilliance-obsessed market. That difference is the whole appeal, and the whole buying challenge.
What makes it antique
Cut by hand from the 1700s through the early 1900s, the old mine cushion carries its era’s fingerprints: a small table, high crown, deep pavilion, big flat culet (visible as an octagon straight through the table), and chunky, slightly asymmetric facets following the rough rather than a formula. Modern cushions splinter light into fine sparkle; antiques throw broad, slow flashes of fire — the checkerboard-of-light effect collectors call “chunky.” Under a jeweler’s halogens the modern stone wins; across a dinner table the antique does.
Reading one beyond the paper
Certificates undersell antiques by design — GIA grades them against modern symmetry ideals, so honest old stones carry “fair” or “good” cut grades that mean nothing about their beauty. Judge instead:
- Face-up life: does it flash boldly as it moves? Video beats stills.
- The culet: a visible culet is period-correct, not damage; enormous ones read as a dead spot — taste, not defect.
- Warmth: most old stones are J–M color because that’s what the mines gave; the cut flatters warmth, and K-color antique pricing is where the value hides.
- Symmetry: slightly out-of-round outlines and off-center culets are provenance. A perfectly symmetric “antique” is usually a modern recut — fine stone, different thing, different price.
Money
Genuine old mine cuts typically run 10–30% under modern cushions of equal weight — the market still pays a premium for laboratory symmetry — though exceptional or documented stones now outrun that discount as supply shrinks: every antique recut into a modern shape leaves one fewer forever. Buy from dealers who photograph in daylight, insist on return windows, and say “old mine” with a straight face. The stone survived a century of owners; it can survive your due diligence.