Fukumitsu Stone Born from Ancient Volcanic Activity
Fukumitsu Stone was formed more than 15 million years ago, during the intense volcanic activity that accompanied the formation of the Japanese archipelago. Volcanic ash and pumice accumulated on the seabed and gradually hardened over an immense period of time, forming a type of tuff known as green tuff.
One of its most distinctive qualities is its softness, which makes it relatively easy to cut and shape. When wet, the stone takes on a gentle blue-green color that gives it a warm and attractive appearance. These qualities have made Fukumitsu Stone a valuable material for architecture and stone monuments since ancient times.
The stone also has excellent moisture-absorbing and sound-absorbing properties. Its surface is relatively smooth, yet it is resistant to slipping even when wet, making it suitable for use as a flooring material, including in bathrooms and on stairs. Fukumitsu Stone continues to be used as a building material today because of these practical qualities.
A Stone That Supported the Culture of Iwami Ginzan
From the late Muromachi period through the Edo period, Fukumitsu Stone was widely distributed as one of the representative building stones of the Iwami region. It had a particularly close connection with Iwami Ginzan Silver Mine, where it was used for numerous structures and objects related to everyday life and religious practices.
Approximately 11,000 stone structures have been identified in the Omori district and within the protected area of Iwami Ginzan, including gravestones, Buddhist statues, waterways, and stone walls. It is believed that Fukumitsu Stone was used for most of them.
The Five Hundred Arhats of Iwami Ginzan
One of the best-known examples is the Five Hundred Arhats at the Iwami Ginzan site. The expressive stone figures were carved from Fukumitsu Stone, whose relatively soft texture allowed artisans to create detailed and delicate sculptures.
After being cut and shaped by skilled stoneworkers, the finished stone was reportedly loaded onto horses and cattle and transported along the rugged Ginzan Kaido road to Omori, approximately 20 kilometers away. Fukumitsu Stone was therefore an essential material supporting both the daily lives and industries of the people who lived around Iwami Ginzan.
A Mysterious Underground Landscape
The greatest attraction of Fukumitsu Stone Quarry is its enormous underground landscape, created through centuries of quarrying. It is one of the relatively rare active quarries in Japan where stone extraction continues today, while parts of the underground site preserve evidence of traditional quarrying techniques.
After following a mountain road and entering the quarry, visitors encounter towering rock walls and a remarkably quiet underground environment. The passages were carved diagonally into the mountain, and countless chisel marks remain on the stone surfaces. These traces provide a tangible connection to more than 400 years of stoneworking history.
The cave-like interior changes in appearance depending on how the light falls on the rock. The pale blue-green walls create an otherworldly atmosphere, making the quarry feel almost like a scene from a science-fiction film.
Bats can sometimes be seen flying through the underground spaces, creating a fascinating environment where nature and human industry coexist. Visits are conducted with a guide, allowing travelers to explore the site while taking appropriate safety precautions.
Fukumitsu Stone in Modern Life
Fukumitsu Stone is valued not only for its historical importance but also for its practical qualities in the modern world.
Viewed closely, the surface contains fine, fiber-like irregularities. These tiny textures help prevent slipping, making the stone suitable for floors and wet areas such as bathrooms.
The stone also has properties that allow it to absorb certain unpleasant gases and odors. It can therefore be used as a deodorizing and drying material. Its effectiveness can be restored simply by drying it in sunlight, allowing it to be reused for a very long time.
Another interesting characteristic is its reaction to heat. At temperatures above 400°C, the stone changes to a reddish-brown color, while temperatures above 1,000°C can turn it black and give it a distinctive sheen. This property has also been utilized in materials associated with Sekishu roof tiles and ceramics.
A Cultural Property of Japan Heritage
Fukumitsu Stone Quarry is included among the cultural properties that make up the Japan Heritage story “The Timeless History Told by the Volcanoes of Iwami: A Journey to the Forests of the Jomon Period and the Silver Mountain.”
The Iwami region is home to a wide variety of geological formations and landscapes created by volcanic activity. Over the centuries, local communities learned how to make use of these natural resources in their daily lives and industries. Fukumitsu Stone is a remarkable example of how volcanic gifts and human ingenuity came together to create a lasting cultural heritage.
The surrounding area also contains distinctive volcanic landscapes, including Onimura’s Oni-iwa Rock and the Tatsugami Rock formations along Hane Coast. Visiting Fukumitsu Stone Quarry offers an opportunity to understand the long relationship between the people of Oda and the geological forces that shaped the land.
A Special Place Where History and Nature Meet
Fukumitsu Stone Quarry is much more than a place where stone is extracted. It preserves the skills of stoneworkers whose traditions date back to the Muromachi period, the history of communities connected with Iwami Ginzan, and the geological power of ancient volcanic activity.
Walking through the quiet underground spaces, visitors can sense the immense passage of time recorded in the stone walls. The combination of nature, history, traditional craftsmanship, and industrial culture makes the quarry a unique destination in the Iwami region.
When visiting Iwami Ginzan or the historic hot spring town of Yunotsu, consider adding Fukumitsu Stone Quarry to your itinerary. Here, you can encounter a remarkable chapter of Japanese stone culture and experience a landscape shaped by both nature and human hands over many centuries.