Maracas

Maraca

Classification	Percussion
Hornbostel–Sachs classification	112.1 (Shaken idiophones or rattles)
Musicians
Machito, Monguito

Maracas ( pronunciation ), sometimes called Rumba shakers, shac-shacs, and various other names, are rattles which appear in many genres of Caribbean and Latin music. Players hold them by their handles, usually in pairs, and shake them. Maracas can't be tuned.

Maracas (Mbaracás), also known as Tamaracas, were rattles of divination, an oracle of the Brazilian Tupinamba Indians, found also with other Indian tribes (Garifuna, Guarani), and on the Orinoco and in Florida. Rattles made from gourds (Lagenaria) are being shaken by the natural grip, while the round calabash (Crescentia) fruits are fitted to a handle. Human hair is sometimes fastened on the top, and a slit is cut in it to represent a mouth, through which their shamans (payes) made it utter its responses. A few pebbles are inserted to make it rattle, and it is crowned with the red feathers of the Goaraz. Every man had his maraca. It was used at their dances, and to heal the sick. Andean curanderos (healers) use maracas in their healing rites.

Modern maraca balls are also made of leather, wood, or plastic.

Robert Plant playing maracas

Guarani shaman holding cross and maraca

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Wikipedia