Ha! Found this at This Site:

    AS CUNCHAS (SHELLS)

ORIGIN AND HISTORY: Pilgrims have used them as a rhythmical instrument since the Middle Ages.

FAMILY TO WHICH IT BELONGS: Percussion (scraper).

MATERIAL: Scallop shells.

DESCRIPTION: It is a device used as a Galician folk instrument made up from two scallop shells because these are the biggest of all.

HOW TO PLAY IT: One shell is struck and scraped across the other to produce sound. They are usually used to accompany the bagpipe and the singing.

TYPE OF SOUND: It is characteristically sharp.

PERSONAL OPINION: We think it is a very typical Galician instrument due to the fact that it is easy to play and has a long tradition.

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