The Chinese abacus (suanpan 算盤) was first recorded in a 190 AD book of the Eastern Han Dynasty and comprised of 2 beads on the upper deck and 5 on the lower, with a minimum of 7 rows. Later instruments added more rows to allow for larger sums.
This pair of sterling silver cufflinks is a perfect working miniature model of the 7 row abacus. It has individual moving beads and an oxidised enclosed back which highlight the beads. The cufflink backing is fixed without any moving parts. It measures 17mm in width and 10mm in height. All sterling silver.