Okazaki stonemasonry Okazaki sekkohin
From master to apprentice, a 400 year tradition
Of hand crafting stone and releasing its inner beauty
Okazaki Sekkohin are stone-carved lanterns and other stone works produced in the area centering on Okazaki City in Aichi Prefecture. They are made using the traditional masonry skills developed in the late stage of the Muromachi period (1336-1573). In the Azuchi-Momoyama period (1568-1603), with the easy availability of good quality Okazaki granite, early versions of today’s lanterns were being made and a masonry industry was developing. Makabe in Ibaraki Prefecture, Aji in Kagawa Pefecture, and Okazaki in Aichi Prefecture are known as the three major stone production centers of Japan. Each area produces its own characteristic stone; the Makabe region has an overwhelming variety of stone types and a high production volume because of its abundant and good quality granite; stone from the Aji region has a very attractive mottled patterning unique to the region, and it is categorized as a world class stone.
Okazaki Stone Carving has a long history and one of its characteristics is the abundance of stone with distinctive marbling such as Okazaki granite. Moreover, in Okazaki, masonry skills and techniques have been developed to such an extent that it is known as the Stone Capital of Japan, and in 1979, Okazaki Stone Carving was designated as a Japanese traditional craft.
In the Azuchi-Momoyama period, Tanaka Yoshimasa, the lord of Okazaki Castle, brought in skilled stonemasons from the Kawachi and Izumi areas to construct walls and moats in the castle town. Thanks to the stonemasons who stayed on, Okazaki’s unique techniques were refined and led to the present-day style of Okazaki Stone Carving.
It was inevitable that the Okazaki region with an abundance of readily available and high quality granite should become a leading stone production center; in the early days masonry workshops were numbered in the dozens, but by the golden age after World War II there were over 350, making stone production a major local industry. The Yahagi River proved an efficient means of transport and contributed to the development of the industry. In the postwar rapid growth period, which was the industry peak, mechanization was making fast progress and work becoming more efficient; this affected the stone crafts as well, and a shift was made from the traditional handwork resulting in improved efficiency. In addition, better road systems and heavier trucks all helped the expansion of the stone craft market, and consequently, the Okazaki Mason Complex was established.
Today, a vocational training school passes down the traditional techniques of Okazaki Stone Carving.
General Production Process
- 1. Jewel
The major products of Okazaki Stone Carving are stone lanterns made of six parts: jewel, lantern roof, light box, central platform, post, and base platform. Each part is first completely carved and then all the pieces are assembled. The basic lantern consists of these six pieces; however, there are also modified types. The following describes the production process for a five-part Oribe-type stone lantern, which is the ikekomi type (buried lantern).
To make the jewel or the top part, the underside is first cut out, followed by finding the center of the rough stone, drawing the diameter of the jewel with sumi ink, and rough chipping. Then, the stone with sumi markings is roughly shaped using a koyasuke hammer, and finished using bishan bush hammers and tataki hammers.
- 2. Lantern Roof (1)
As the first step, the upperside and underside are carved. After the center of the rough stone is determined, the stone is carved, and a square is drawn with sumi ink on the underside. In the same way as the jewel, rough chipping, ink marking, and rough shaping are carried out.
- 3. Lantern Roof (2)
After rough shaping, bishan and tataki hammers are used to give a final finish to the lantern roof.
- 4. Light Box (1)
For the light box as well, the upperside and underside are carved, and the rough stone is machine-cut to the prescribed dimensions.
- 5. Light Box (2)
After finding the center of the rough stone, marking lines with sumi ink, and rough chipping, a tetrahedron is created by rough shaping. A hollow is carved and lines are marked with sumi ink.
- 6. Light Box (3)
By making full use of such tools as tataki hammers, bishan bush hammers, and kobera small chisels, the light box is completed.
- 7. Central Platform
The central platform is carved following the steps as above.
- 8. Post (1)
For the post, after the same process is repeated up to rough chipping, using different tools such as setto hammers and chisels, the stone is roughly shaped.
- 9. Post (2)
On the upper part of the post, a simple design is engraved using a small chisel, and on the lower part, a Buddhist image. Finally, a bishan bush hammer is used to finish the post.
- 10. Completion
All parts are assembled to complete the stone lantern.