
Walk away with garnets, amethysts, rubies and sapphires at this little-known tourist spot.
Once you become an adult, it can feel like there are fewer things you can enjoy with the same unabashed freedom that you once had as a child. However, the other day, our reporter Maro came across something that nurtured her inner child for the first time in a long while, and it was located at a tourist facility in Yamanashi Prefecture called Saiseki no Kura.
▼ To be accurate, the place goes by the offical name “Koushuu Tennenseki Koubou Saiseki no Kura” (“Yamanashi Natural Stone Workshop Unpolished Gem Warehouse“), with “Koushuu” being the old name for Yamanashi.

As the name suggests, this facility specialises in stones and gems, which is apt, seeing as Yamanashi Prefecture has long had a thriving jewellery industry, and even has a gem museum dedicated to precious natural ores from all over the world. What makes Saiseki no Kura so popular is the fact that it offers a Gem Hunt for Adults, where you can rifle through a collection of small rocks and take any semi-precious stones and gems you find home with you!
▼ Saiseki no Kura is located about three minutes by car from JR Isawa Onsen Station.

When Maro arrived at the warehouse, which is free to enter, she first made her way past a collection of glistening natural ores, including an amethyst that was larger than her.


The gem hunt is located in a building next to this one, so that’s where she headed to next. This is where you’ll find a gem hunt for children and one for adults, the latter of which is divided into several courses, depending on the value of gems that can be found.

Maro opted for the standard 2,200 yen (US$15.40) course, which is guaranteed to contain one of nine types of gemstones polished by an artisan, in amongst other small chipped stones and craft stone replicas.
▼ The Gem Hunt has a time limit of 30 minutes, so time is a top priority for the gem hunter.

▼ The first task is to choose your excavation container.

The gemstones have already been buried by staff, so what kind of jewels you unearth depends on the container you choose. Each bowl has a comment attached to it, so you can use your intuition to help you make the all-important choice.
▼ “Are you sure it’s me — you won’t regret it?”

Mari chose a container with a picture of a mysterious man on it that really stood out to her.

Once she’d made her choice, there was no time to waste, as she only had half an hour to search for gems. Deftly using the spoon and tweezers provided, Maro dug through the stones to discover the hidden jewels.

The great thing about Gem Hunting for Adults is you can actually find a lot of gems. Just use the back of the spoon and the tweezers to rifle through the stones and you’ll find a bevy of colourful gems.

Maro couldn’t believe how much she’d harvested in just 10 minutes — there were major finds, like amethysts and crystals, in amongst other colourful stones. Many of these natural stones had holes in them, so they could easily be made into accessories.
▼ After about 15 minutes of digging with all her might, Maro found a gem that shone like none other.

The deep red stone was a garnet, which made Maro want to jump up and down in delight. This was the most coveted gem in her price category, so she was relieved to find it within the time limit.
She still had time for more digging, though, which was good because the excavation method required quite a bit of time and patience.

The trick to success, according to Maro, is to break up the pile with the back of the spoon and pick only the stones you want with the tweezers. Since you can only use these two implements, you can’t get everything you want in just 30 minutes, so you have to be selective to a certain extent.
▼ After digging for a few more minutes, Maro came across…another garnet!

Ordinarily, there’s only one gemstone per container, but on rare occasions, the person who went before you may have missed out on finding the gem, in which case there might be two gemstones in the container once staff have added to it.
Maro was super lucky to have found not one but two garnets, so she said a silent thanks to the mystery man who’d enticed her over to the container with the message, “You have a good hunch, don’t you? I don’t mind letting you choose.”

Maro continued to mine for gems, concentrating so hard on the task that when it was over her shoulders, neck, and eyes were sore. The 30 minutes seemed to pass by in the blink of an eye, but she was glad it ended when it did because if she’d continued any longer she might have suffered even more aches and pains. Still, it was so much fun that she became totally engrossed in the activity and totally lost track of time, and what she went home with was far more than anything she could’ve dreamed of.
▼ The tray in the back shows what her friend mined in the 30 minutes, while the tray in front is Maro’s haul.

All the stones can be taken home as is, or they can be processed into accessories like resin art or jewellery for an additional fee. Since Maro was able to collect two garnets, she wanted to turn her gems into earrings, but she didn’t have time to wait for them to be made or pick them up at a later date so she decided to make them herself at home.
She left totally happy and satisfied, praising it as the best tourist activity in Yamanashi Prefecture. Those who opt for the most expensive 10,000-yen course can even unearth rubies and sapphires, and different jewels appear every season, so you’ll want to come back again and again!
▼ Other stones you can find include topaz and peridot.

Children aged from three and up to 6th grade can also join in the fun with a gem hunt of their own, priced at 1,100 yen per person.

▼ Aside from the garnets, Maro’s other favourite finds from the day were these amethysts in various shapes.

While it takes about 30 minutes to hunt for gems, if you include walking around the museum and browsing the store, you can spend a good two to three hours here. Both adults and kids will love the fun of the hunt, and staff are incredibly kind and friendly, so Maro can’t wait to visit again in future.
It’s one of many hidden gems you can find in Yamanashi, which is also home to one half of Mt Fuji and its bright blue Fuji curry.
Site information
Koushuu Tennenseki Koubou Saiseki no Kura / 甲州天然石工房 彩石の蔵
Address: Yamanashi-ken, Fuefuki-shi, Isawa-cho, Kubonakajima 122-1
山梨県笛吹市石和町窪中島122-1
Hours: 8:30 a.m.-5:00 p.m. (Gen Hunting reception open until 4:15 p.m.)
Open year-round
Website
Images © SoraNews24
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[ Read in Japanese ]

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