China's first abacus museum has opened with a collection of over 600 abaci in Qixian County of North China's Shanxi Province.

The abaci, all collected by Zhou Baolin, a local resident, vary in standards, shapes, materials and lengths.

In terms of standards, the collection contains seven-bead models of two-up, five-down; five-bead models of one-up, four-down;and nine-bead models, one-up, three-middle and five-down.

The abaci differ in shapes from square, octagon, trapezia, triangle to double-fish, and the materials also have a wide variety including gold, silver, copper, iron, bone, jade, agate and crystal.

Their lengths range from six meters (19.6 ft) to one centimeter (0.4 in) with the longest one allowing 12 people to work together and the smallest adecoration.

The elite collection contains an ivory seven-shift abacus with seven rhombic beads, two-up and five-down from the Ming Dynasty (1368-1644), a five-shift abacus with copper rods and red agate

beads, one-up and four-down, and abaci once used by Emperor Qianlong of the Qing Dynasty (1644-1911) and the Empress Cixi of the late Qing Dynasty.

The 11-shift abacus used by Emperor Qianlong caps the collection with a gold frame, more than 20 colorful gems and 77 china beads outlined with various bright flower designs.

Nowadays abaci serve as a complement to computers in China's finance and accounting sectors.

Chinese craftsmen have built a spectacular four-storey pavilion with 668 abaci, copying the ancient Danfengge Pavilion, in Qixian county.

Experts said that abaci appeared and faded out in many countries, however they survived in China, where their origin was previously believed to be in the Eastern Han Dynasty (AD 25-220), based on the earliest record found in an arithmetic book from that period.

However the finding of eighty-six clay beads from the Western Zhou Dynasty (1000-771 BC), identified as those used for calculation, dates the origin of the abacus to at least 2,700 years ago.

(Xinhua News Agency April 19, 2002)