Latus clavus

In Ancient Roman regalia, a laticlave, or clavus, was a broad stripe or band of purple on the fore part of the tunic, worn by senators as an emblem of office, from which the difference of the tunica angusticlavia, and laticlavia.

This ornament, according to some, was called clavus ("nail") as being set with little round plates of gold, or silver, like the heads of nails.

Cantelius maintained that the clavus consisted of a kind of purple flowers, sewn upon the cloth.

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