Celtic brooch

Ring-and-pin clothing fastener

The Celtic brooch, more properly called the penannular brooch, and its closely related type, the pseudo-penannular brooch, are types of brooch clothes fasteners, often rather large; penannular means formed as an incomplete ring. They are especially associated with the beginning of the Early Medieval period in Ireland and Britain, although they are found in other times and places—for example, forming part of traditional female dress in areas in modern North Africa.

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