Picks for playing a Japanese stringed instrument have been developed using a biomass material made from plant fibers.

Picks for the instrument, a koto, have traditionally been made of ivory. But an international treaty bans the global trade of that material.

The new picks are made of Cellulose Nano Fiber. They are being sold by trading house Itochu, an engineering plastics manufacturer, and a maker of traditional Japanese musical instruments. The picks cost more than five times as much as plastic ones.

Professional koto player Leo said, "The new picks are closest to ivory in terms of sound and warmth."

The developers say they plan to use the same material for the shamisen, another traditional Japanese instrument.

The Convention on International Trade in Endangered Species has banned the cross-border ivory trade since 1990.

But in Japan, the domestic trade for use in traditional musical instruments has been allowed on a limited basis and under strict legal control, due to difficulties in finding alternative materials.

The convention is opening a meeting in Panama on Monday. The members are expected to discuss ivory trade control in Japan and other countries where limited domestic trade is still allowed.