In Japan's picturesque Ago Bay, a couple sits in a little hut picking out oysters from a net, cleaning them carefully one-by-one before replacing them gently back in the water.
Their hope: in several months, these oysters will produce a glistening white pearl from a cultured farming technique invented in Japan that is in decline as experts die out in the ageing country.
In 1893, an Ago Bay local called Kokichi Mikimoto became worried the oyster pearls avidly sought in his waters were becoming extinct.
After several setbacks -- including a bacterial virus that decimated his crop -- Mikimoto finally hit the jackpot: one day in July 1893 a semi-spherical pearl appeared, clinging to the oyster.
A decade or so later, he had refined his method to produce a perfectly round specimen and immediately patented his technique -- the cultured pearl.
Top five percent
The Sakaguchi family has been crafting these valuable pearls between three and 10 millimetres in diametre for three generations. Kasuhiro, 73, and Misayo, 68, are now supported by daughter Ruriko.
"Our job is to look after the oysters as well as we can for three to four years," explained the energetic 43-year-old Ruriko, sporting an apron and headscarf.
The pearls are harvested in December, when the water is around 15 degrees, said Ruriko. "Below this, the pearl will lack strength. Above that, it will lack shine," she explained.
It is a thankless task. Of the 100,000 oysters harvested annually, half die immediately after the operation.
The vast majority produce either mediocre pearls or nothing at all. Only around five percent of the oysters harvested will result in pearls of sufficient quality to adorn the windows of chic jewellers far away in Tokyo.
A farmer of the Sakaguchi Akoya pearl farm displays oysters with pearls on a table in Shima.
'Family heirloom'
The Sakaguchis are lucky to have Ruriko take up the family trade, which is suffering -- like many other traditional Japanese crafts -- from an ageing population and a flight from the country to booming cities.
The number of specialised pearl farmers has dropped from 3,760 in the 1960s to just 680 in 2013, according to the most recent data from the Fisheries Agency.
"The key is the winter season in Japan. It gives the pearls a better shine and sets them apart from the rest of world," Nakamura told AFP.
That quality is on glittering display at the luxurious, multistory flagship store of Mikimoto, in the plush Tokyo district of Ginza.
Here a mannequin wears a priceless pearl necklace but pearls can range from a few hundred to a million dollars.
"For the Japanese, pearls are a family heirloom. We give them as necklaces to women about to marry or as earrings or rings," said Mikimoto boss Hiroshi Yoshida.
Agence France-Presse