Yupana, stone to calculate (illustration).

Yupanas and 'pallares' beans (recreation).

Yupana. Counting stone. Imperio Inka, Andes Centrales del Perú, 1400-1532 d.C. Colección Museo Nacional de Arqueología, Antropología e Historia del Perú-Ministerio de Cultura de Perú, L-008450.

Yupana. Counting stone. Imperio Inka, Andes Centrales del Perú, 1400-1532 d.C. Colección Museo Nacional de Arqueología, Antropología e Historia del Perú-Ministerio de Cultura de Perú, L-020392.

Counting units. Pallar beans. Serving dish, ceramic. Nasca, costa sur del Perú 400-700 d.C. Colección Museo Chileno de Arte Precolombino, 3597.

Counting units. Pallar beans. Cup, ceramic. Nasca, costa sur del Perú, 400-700 d.C. Colección Museo Colchagua, PE-MCOL 05.

Yupanas and pallares: Stones to calculate

A yupana (from the term yupay, to count) is a tablet similar to an abacus that was used to complement the use of quipus. In Tawantinsuyu these tablets had a ritual purpose—they were employed to record songs and also functioned as calculators. Yupanas consist of a system of compartments in which stones or pallar beans were placed to denote numbers in a complex numeric notation system that is still used in some schools in Peru today to teach mathematics.