Under a magnifying glass, more than 100 Chinese characters of shou (longevity) in different fonts manage to set themselves clearly apart from one another on a cloth the size of a match box.

They were all embroidered by Zhao Hongyu, 66, stitch by stitch on the tiny cloth, forming a part of her masterpiece Baishoutu (Hundred Longevity Painting), which features a benevolent-looking man in his advanced years and such auspicious patterns as peaches and deer.

Zhao astounded many people in 1982 when she completed the piece. Its patterns were embroidered on both the front and back and looked exactly the same.

It was widely considered an innovation of Wuxi fine embroidery, which had traditionally been done on just one side.

A branch of Su embroidery originating from East China's Jiangsu province, the art from Wuxi, at the southern part of the province, boasts a history of more than 2,000 years and was listed as a national intangible cultural heritage in 2008.

The art form distinguishes itself through its intricate utilization of needlework, thread, fabric and color, demanding elevated technical proficiency and introducing additional layers of complexity.