The price of silk cocoons, the raw material for the fabric used in expensive items of clothing, has doubled since the start of 2009 to Rmb92,700 ($13,570) a tonne in mid-April, according to the China Cocoon and Silk Exchange.
European merchants and weavers said the price of raw silk, the variety traded internationally, had followed a similar trend.
“It is rising every day, every week,” said Christian Morel Journel, a silk merchant in Lyon, France.
The urbanisation of the key silk-producing region around Shanghai has reduced the land available for mulberry trees, whose leaves are the only thing silk worms eat.
“It’s as if you had a very large city in Champagne on the soil of the famous wine,” Mr Morel Journel bemoaned.