An escarbuncle is a stylized heraldic charge, representing the boss and reinforcing bars on a shield. It is normally of eight spokes, with the ends fleury, as in the illustration; this form is found very early, in the arms of the Counts (later Dukes) of Cleves, c.1275 [Asp2 190; also Gelre 93]. Escarbuncles of six are also found in period arms, as well as pometty ends; such cases are explicitly blazoned. (Sometimes, the default fleury ends are explicitly blazoned as well.)
Escarbuncles may also be constructed by conjoining other charges: the arms of the Kings of Navarre, from the mid-14th Century, had an escarbuncle of chains. In Society heraldry, other charges have been employed as well: an “escarbuncle of six swords, conjoined at the points”, for example.
The King of Æthelmearc bears: Gules, an escarbuncle argent within a laurel wreath and in chief a coronet Or.
Lorna of Leeds bears: Or, an escarbuncle of six flory azure.
Alicia of Ravenserespourne bears: Sable, three escarbuncles one and two Or.
Ferran de Montfery bears: Argent, an escarbuncle of six spears offset deasil gules.