CASTANET The most common classification of percussion instruments divides them into 2 categories, of definite pitch and of indefinite pitch. The latter includes most of the smaller percussion instruments, like triangle, tambourine, castanets, cymbal, gong and sleigh bells. Tracing its origin to the Spanish word for chestnut - "castane", the castanet is made up of 2 pieces of shell-like hard wood tied together with a piece of string. The modern orchestral castanets are, however, hinged on the end of a handle, by means of which they are shaken like a rattle. The castanets are used most often to highlight the rhythm of Spanish music, especially that of Spanish dance music.