Japanese Semiprecious Stone Craftwork | Traditional Gemstone Carving and Polishing

 

1. Koshu crystal and precious stones carving

The Tradition of Koshu Crystal and Gemstone Carving

In Kofu, a city in Yamanashi Prefecture, there's a long-standing craft that turns raw gemstones into detailed crystal carvings. Known in Japanese as Koshu Suisho Kiseki Zaiku, this type of work focuses on carving natural crystal and semiprecious stones by hand. It’s a slow, careful process that turns hard, transparent stones into art pieces with vivid colors and sharp detail. These carvings last a long time and hold their shine, making them both decorative and durable.

Kofu has been tied to this craft for centuries, mostly because of its natural supply of crystal. That local resource helped build a reputation for high-quality gemstone work. Koshu carvings cover a wide range of styles, from energetic animal figures and symbolic dragons to playful characters popular with kids. Each piece starts with cutting and shaping the stone. From there, it goes through rounds of grinding and polishing until it reaches a clean, bright finish.

Crystal is hard and brittle. That means the person carving it has to work slowly and with a steady hand. Even a small mistake can crack the stone. One of the most complex local techniques is called yukan. This involves carving a single piece of crystal into a chain-like form without breaking it. To pull off something that detailed, you need years of experience and a deep understanding of both the material and the method.

The History Behind Koshu Stone Carving

This craft goes way back. It started during the Heian period, between 794 and 1185 CE, when clear crystals were first found in the Mitake Shosenkyo Gorge and around Mt. Kinpu in northern Yamanashi. Back then, crystal was pretty as it was considered sacred. People used it in rituals and as spiritual objects.

Things changed in the 1800s, between 1830 and 1844, when experts from Kyoto came to Kofu to teach locals how to hand-polish gemstones. They brought techniques from the Tamatsukuri area, which helped local artisans develop their own style. One method involved using emery powder on an iron plate to grind and smooth each stone by hand. Once this method caught on, people started making decorative objects instead of just tools or religious pieces.

In 1876, Shiro Fujimura, who was then the governor of Yamanashi, pushed to improve the craft even further. He set up a public crystal workshop in Kofu and sent craftsmen to China to learn more techniques. That move raised the skill level across the region.

By the time the Meiji period ended, though, local crystal was running low. So, during the Taisho period from 1912 to 1926, the industry moved toward processing imported stones like agate, diamonds, and quartz. Since the region already had strong polishing skills, the move went smoothly. When the area upgraded to electric tools, Kofu also started making fine parts for machines using gemstone materials.

After World War II, most of what they made (around 80%) was shipped overseas. But in 1971, when the U.S. dollar dropped in value, exports slowed. That’s when the focus turned back to Japan. Craftsmen began blending old techniques with new tools to make detailed, high-quality pieces for the local market.

Now, Koshu crystal carving is a mix of old and new. The tradition hasn’t faded. If anything, it’s evolved. The skill, care, and vision needed to keep this craft alive are still passed down. Every piece tells a story of beauty, and of survival, skill, and change.

How Koshu Crystal and Gemstone Carvings Are Made

Choosing the Right Stone

Everything starts with picking the right gemstone. The materials used for Koshu carvings include crystal, jade, agate, and tiger's eye. These are hard stones that take a long time to shape. Crystal, for example, is more than twice as hard as glass, so cutting it is no small task. This step requires a sharp eye and years of experience.

Out of dozens of rough stones, only a few will make the cut. The craftsman has to consider the polishing method and how each type of stone reacts to grinding and carving. Most stones are imported, and each has its own traits. The artisan has to spot flaws like internal cracks or cloudy areas right from the start. If they miss one, the stone could break later during carving.

Cutting the Stone to Shape

After choosing the stone, it's trimmed down to a workable size. The artisan checks it again for defects and figures out which sections are usable. It’s important to avoid weak spots. Once they pick the best part of the stone, they draw guidelines on the surface. These lines mark where the cuts will go. A powerful cutting machine is then used to slice the stone along these lines.

Planning the Design

Next comes the design. The artist sketches a draft directly on the cut stone. They use the natural color and patterns of the stone to their advantage. If the piece is a Buddha statue, for example, they’ll make sure the clearest, most attractive section of the stone ends up in the face. The shoulders, arms, and legs are also drawn out carefully so the figure stays balanced. The proportions follow a traditional layout, like making sure the figure is six heads tall.

Rough Shaping

Once the sketch is ready, the stone goes through rough shaping. A high-speed diamond drill follows the drawn lines and starts to carve the basic form. One small mistake at this stage can ruin the whole piece. This part of the process is all about control and focus.

Smoothing the Shape

After rough shaping, the surface needs to be refined. The artisan uses several steel discs spinning at high speeds to scrape the stone into a more detailed shape. This is done in four stages. Each round of scraping uses emery powder, starting with coarse grains and moving to finer ones. This step helps form the curves and details more clearly.

Polishing the Surface

Now that the piece has its final shape, it’s time to polish it. The rough surface is smoothed out using wooden discs. First, a hardwood disc is used to even out the surface. Then softer woods like willow or paulownia help bring out a clean, glossy finish. A final polish with fine sand smooths it even more.

Final Touches

The last step brings everything together. A round whetstone and chromic polishing powder are placed in a machine that rotates at high speed. The piece goes in and is polished until it shines. Once that’s done, the artisan steps in for the final hand-finish. They polish small parts and carve details with precision, using everything they’ve learned over the years to turn the raw stone into a complete piece of art.

 

2. Wakasa agate craft

Wakasa Agate Craft, called Wakasa Meno Zaiku in Japanese, is a type of handmade agate work made in Obama, a city in Fukui Prefecture. This quiet coastal region has a long history of expert craftsmanship, shaped by its natural surroundings and close ties to old cultural centers like Kyoto and Nara.

Fukui is known for many traditional crafts. In Echizen, you'll find hand-forged knives and strong washi paper made using mountain water and local plants. Along Wakasa Bay, fishing villages helped create unique coastal items like lacquered chopsticks decorated with mother-of-pearl. These crafts were passed down through families for generations and are still made today with care and precision.

Agate has been valued for a long time in Japan. It's one of the seven sacred treasures described in Buddhist scripture, said to decorate the peaceful paradise of the Pure Land. Wakasa Agate Craft stands out for its rich red glow. That color comes from a special heating process that uses iron to draw out the stone’s natural depth. This technique gives each piece a deep reddish-brown tone that shows off the fine details of the carving.

These handmade agate pieces aren’t just for display. They include items used every day, like chopstick rests and small soup bowls. But they also include decorative carvings of animals like roosters and carp, which are often given as gifts. Each piece is shaped, polished, and finished by hand, showing off both beauty and skill.

The roots of Wakasa Agate Craft go back about 270 years. Sometime between 1716 and 1735, a craftsman named Kichibei Takayama returned to Wakasa after learning optical work in Naniwa, now called Osaka. Using what he had learned, he began making agate beads. That was the beginning of the local gemstone craft.

The style changed during the early Meiji era, which lasted from 1868 to 1912. That’s when the simple beads were developed into more detailed works. One key figure was Heisuke Nakagawa, a craftsman from Wakasa who worked to push the craft forward. He helped turn it from basic jewelry into elaborate carvings, like the lifelike roosters and flowing carp designs that define the style today.

Over time, Wakasa Agate Craft came to be seen not just as a local product but as a form of art. Pieces were shown at exhibitions across Japan and in other countries. In 1976, the Japanese government officially recognized it as a Traditional Craft, giving it national cultural status.

Today, Wakasa Agate Craft remains one of Japan’s oldest gemstone traditions. It blends natural beauty with handmade skill, offering both everyday objects and artistic carvings that hold deep meaning and long history.

How Wakasa Agate Craft Is Made: Traditional Stonework Process from Japan

Using Agate Gemstones from Brazil and Hokkaido

Wakasa Agate Craft is made using real agate. Back in the Meiji period, from 1868 to 1912, most of the agate used came from Hokkaido. But once those sources started to run low, the makers began using Brazilian agate instead. That switch helped the craft continue without losing quality. Today, most Wakasa pieces are still made using Brazilian gemstones.

Sorting and Selecting the Best Quality Stones

Each gemstone goes through a careful inspection before any work begins. The craftsperson checks the color, clarity, and patterns in the stone. These details help decide what kind of item it will become. Solid agate is usually picked for sculptures and figures, while hollow stones are better suited for accessories and smaller designs.

Cutting the Rough Shape with Precision Tools

Once the stone is chosen, it gets trimmed into a rough shape using a bow-style cutting machine. This tool doesn’t have a sharp blade. Instead, it uses a mix of ground sand and water, called slurry, to slowly wear through the stone. The artisan has to keep the slurry flowing evenly during the cut. This step lays the foundation for the entire piece.

Letting the Stone Oxidize Naturally

After the rough cut, the stone gets left out in the open air. This lets it oxidize over time. That natural process is important because it helps bring out the rich red tone when the stone is heated later. It’s a slow but vital part of the craft.

Heating the Agate to Unlock Its Deep Red Color

Heating is what gives Wakasa Agate its famous reddish glow. The stone gets buried in ash and slowly heated with charcoal. The artisan repeats this process carefully to bring out the ideal color. It’s a tricky step. If the stone gets too hot, it can crack. If the heat is too low, the stone stays dull and cloudy. Some makers now use electric ovens at about 300 degrees Celsius for several days to control the process better.

Marking and Cutting for Final Design

Once the stone is heated and ready, a rough outline is drawn on it using graphite. That line shows which parts need to be removed before carving. Then, the artisan cuts away the extra parts, trimming it closer to its final form.

Chipping the Stone by Hand

Shaping the stone starts with a process called chipping. The craftsperson uses a tool called a tetsuya, which is tapped lightly with a small hammer. The stone is held steady between the artisan’s knees. Bit by bit, they chip away at it to form the basic shape.

Refining the Shape with Sand Polishing

After chipping, the stone still needs more shaping. The artisan smooths the surface using rough sand, then gradually uses finer sand to get cleaner lines and details. This step is where the form starts to look polished and finished.

Final Polishing for a Smooth, Shiny Surface

The last part of the process is polishing. First, the surface gets scrubbed with finely ground mud. Then polishing powder is used to create a glossy finish. This stage takes patience. For complex designs, it can take over a month to get it right. But that careful work is what gives Wakasa Agate its smooth surface and glowing, see-through look.

Every step of this process relies on the artisan’s skill, timing, and judgment. That’s what makes each piece unique. It’s not just stonework. It’s tradition, technique, and history carved into a gemstone.