culet

Noun

culet (plural culets)

1. (historical) A component of armor, consisting of overlapping plates designed to protect the buttocks.
   • The Turk prosecuted his advantage to the uttermost of his power; yet the other[…]not onely avoided the Turkes violence, but having drawne his Faulchion, pierced the Turke so under the Culets thorow backe and body, that although he alighted from his horse, he stood not long ere hee lost his head, as...1630, John Smith, True travels, Kupperman, published 1988, page 49

   Synonyms:

   garde de rein, hoguine

2. A small, flat face often cut at the base of a brilliant-cut gemstone.
   • The common diamond cut for high pressure work is the modified brilliant cut (see Fig. 1) in which the point of a brilliant cut diamond (i.e., the type of diamond commonly found in an engagement ring) is lopped off to provide a flat surface, called a culet, for pressure transmission. Two opposed...1999, John W. Kenney, III, 7. Pressure Effects on Emissive Materials, D. Max Roundhill, John P. Fackler Jr. (editors), Optoelectronic Properties of Inorganic Compounds, Plenum Press, page 234
   • The culet looks like a point at the bottom of the stone, but it is normally another facet—a tiny, flat, polished surface. This facet should be small or very small. A small or very small culet won't be noticeable from the top. Some diamonds today are actually pointed. This means that there really is...2006, Antoinette Leonard Matlins, Diamonds: The Antoinette Matlins Buying Guide, LongHill Partners (GemStone Press), 2nd Edition, page 85