A type of jewel in the form of a capital letter. An important example is the founder's jewel featuring the letter M. Another is a Saxony locket in the form of the letter E. Another is in the form of a B, referring to Blanca, the mother of King Haakon of Denmark, who in 1372 redeemed it from pawn. A brooch shaped like the letter M and another like the letter B are listed in the inventory made in 1328 of the jewels of Queen Clementia, second wife of Louis X of France.
An English example in the form of an A was recorded in 1875. Such letter jewels are known to have been made in the 14th century, but surviving examples are rare.
From: An Illustrated Dictionary of Jewelry, autor: Harold Newman, publishers: Thames and Hudson