Rita and I woke up at Aomi’s home in Toba, under a clear, cloudless sky whose blue seemed drawn from the whole world.

Since moving here ten years ago, Aomi has personally worked on this traditional Japanese-style house, which is incredibly spacious — a size unimaginable in cities. It even has three guest rooms. Assigned a six-tatami mat room on the first floor, I sprawled out on my futon and slept soundly all night without dreaming. It’s an entirely different world from the tiny bedroom in my Brooklyn apartment, where my partner and I jostle together each night as we fall asleep. I found myself deeply impressed that Aomi’s intuitive call to return to Japan proved perfect.

Aomi usually starts diving for seafood at seven in the morning, but today she arranged to accompany us on our research interviews. She took the wheel of our rental car and glided along the coastal road. I sat in the passenger seat, taking in the lush greenery spreading inland, while Rita kept the rear window down, letting the sea breeze fill the car just like yesterday.

Following Rita, I introduced myself. Aomi then shook Ms. Yaegashi’s hand with the same firm confidence she had shown in her US trading career, saying, “I’m Aomi, an ama diver.”

When Ms. Yaegashi learned that the two visitors from New York and the local ama diver were friends, she was not just surprised, but genuinely impressed. “That’s amazing. It feels like this place and Manhattan are suddenly connected,” she said excitedly.

Next, we were introduced to Mr. Yamauchi, Manager of the Pearl Farm. Since his position has been held by his family for two generations, he has inherited complete expertise in cultured pearls. There is no one better than him to show us around this place.

What looked like an old-fashioned elementary school turned out to be the workshop. I couldn’t hide my amazement, having pictured it as a sterile, lab-like space. It’s a heartwarming surprise that the starting point of elegant jewellery captivating people worldwide lies within this nostalgic wooden building.

“Is this where Miss Misaki Takemoto works?”

Misaki, the young artisan we met at last night’s get-together left early without hesitation, saying, “I need to get going because of work tomorrow.” She said she is in charge of “nucleation” at the farm. I wanted to ask in advance what that work entails, but her mother, Nagisa, insisted I wait until the tour, saying that nothing beats seeing it for yourself. So I have come looking forward to it.

“Yes, Miss Takemoto is hard at work right now. Let’s go look,” Mr. Yamauchi said, and we followed along.

“What I’m doing right now is ‘nucleation’ — the process Rita asked about yesterday. From the adjacent table, I take a small piece of mantle tissue from an Akoya oyster, called the ‘piece,’ and insert it into another Akoya oyster along with a ‘nucleus’ made from a shell bead.”

Rita and I leaned in as much as we could to carefully watch the mystical task.

An Akoya oyster is secured to a stand on the worktable. The “nucleus” is inserted into the oyster’s slightly opened shell, along with the “piece,” using a stick resembling a knitting needle. Misaki’s hands move with great dexterity, efficiently performing one nucleation after another.

Once nucleated, we learned that the oysters are returned to the bay where pearls form inside them over the course of many years.