BBC News business reporter in Shanghai, China
The Deching region of China is home to one of the country's most traditional industries, pearl farming.
September is harvest time for China's pearls
Its abundant fresh water lakes are filled with China's most prized pearls.
From a distance you can see hundreds of white floats bobbing up and down on the lakes' surface.
These mark out the many fishing nets full of pearl clams lying underneath, carefully tied to bamboo poles.
September is harvest time and right now the pearl farmers need to make their final checks on the crop.
It is vital they make sure there is no infection in the water as any disease or errant weeds could destroy the whole harvest and at least three years work.
There are about ten pearl farms in Deching.
One of the largest belongs to Osmun pearl company, which is run by Shen Zhirong. The success of his business is testimony to how the industry has grown in China.
Workers sort through pearls by colour, shape and size
China is now the largest fresh water pearl producer in the world. Almost a thousand tonnes of pearls are produced each year by about 300,000 workers around China.
China began to culture the common pearl in the thirteenth century, but surprisingly the technology for producing cultured pearls was only perfected in the 1960s.
Back then, the quality of Chinese fresh water pearls was poor. Known as "rice pearls", their irregular shapes and sizes were unable to compete with the beautifully round, iridescent pearls of Japan.
China has cultivated its own implantable mussels and perfected the technique for growing larger and rounder cultured pearls in a variety of sizes and colours. Its clams are painstakingly implanted with tiny bits of shell or other substance which then form into a pearl over the years.
Mr Shen's farm has expanded and he rarely has time to visit his business.
These days he spends most of his time in the processing plants.
Many of China's pearls are used for making medicine and makeup
Previously, the pearls were processed in Hong Kong and Japan, but the Chinese pearl processing industry has grown, largely thanks to the country's low cost skilled workforce.
Workers at Mr Shen's factory sort through the pearls by colour, shape and size. Only 10% of all pearls produced are used in jewellery, the rest are crushed and made into medicine and make up. Crushed pearls are used in skin creams, as pale women are considered beautiful.
"We do not want to waste the pearls so we are really developing our makeup and health products. In China, we believe that the pearl is excellent for health. With such a huge population, we believe the market for these products is enormous," said Mr Shen.
It is these offshoot industries that look set to further modernise China's pearl industry for the global market. This is a fast developing country which wants even its traditional industries to lead the world.