China"s most ancient gift to the world, silk, arrived long before gunpowder, paper and print-making. This coveted fabric predated Christ and Buddha. Silk startled the world: Lenient ancient Romans banned it as sexy and immoral. Durable,useful and elegant, it is one of the oldest fibers known to man. Production remained a Chinese secret until 550 when two Nestorian monks, risking their lives,smuggled out silkworms hidden in bam-boo canes. They presented the pupas to the Byzantine Emperor Justinian in Constantinople as tribute.