Saturated yellow, from nitrogen present when the crystal formed. Where a light yellow stone hints, these commit- the color carries across a room and holds under any light. Cut matters more here than in a colorless diamond, because proportions either concentrate the color or wash it out.

Named for the way its facets open from a central point. Domed above, flat below, no pavilion and no culet. Cut since the sixteenth century and never about brilliance- it glows rather than flashes. The flat base gives it a broad face for its weight, and the shallow depth lets you see into the stone rather than off it.