Hagi glass is a glass craft made at 萩ガラス工房 (Hagi Garasu Kobo) in Hagi City, Yamaguchi Prefecture. In Hagi at the end of the Edo period (Bakumatsu), 'Hagi Garasu' (萩硝子), created through repeated research by the chemist Nakajima Jihei, was produced, but it died out after only a few years. 萩ガラス工房, founded in 1992 (Heisei 4), studied the production method based on old documents and, adding modern techniques, revived it as Hagi glass. The raw material is quartz basalt mined on Mt. Kasayama in Hagi City. The studio carries out the entire process in-house, from crushing the rock to making the products. Its representative products are 'basalt glass', which is pale green from the iron contained in the rock, and 'Uchi-hibi Kannyu glass' (inner-crackle glass), in which cracks are sealed inside a three-layer glass. It is a hard potash glass that is said to resist scratches and not to turn cloudy white even after long use. At the studio, visitors can try free-blown glassblowing (chubuki), accessory making and engraving.
Origin
The roots of Hagi glass lie in 'Hagi Garasu', which was made in Hagi at the end of the Edo period. It is said to have been created through repeated research by Nakajima Jihei, an interpreter who was also a chemist, and it was a highly transparent and durable glass. The raw material at the time is said to have been crystal stone mined at 江船山 in Mine City. It is said to have been prized by Lord Shimazu of the Satsuma Domain as well, but it died out amid the unsettled conditions that followed the Joi War (the fighting to expel foreigners).
History
The person who worked to revive Hagi Garasu was Mr. 藤田 (Fujita), the president of 萩ガラス工房, who had been engaged in ceramics-related work. He learned of the Bakumatsu-era Hagi Garasu while working in Tokyo, and after returning to Hagi he read old documents and studied the production methods of the time. Drawing on the knowledge he had built up in the ceramics industry and on modern technology, he founded 萩ガラス工房 in 1992 (Heisei 4) and revived it as Hagi glass. The revival came after a gap said to be 130 or even 150 years since the method had died out.
Features
The quartz basalt used as the raw material is said to be found in Japan only on Mt. Kasayama in Hagi City. Mt. Kasayama is 112 m high and is sometimes called the smallest volcano in Japan. The pale green color is not added coloring but a natural color produced by the iron oxide contained in the stone. It is a hard potash glass rich in potassium and is melted at high temperatures of 1,500°C or more. It is said to be more scratch-resistant than ordinary soda glass and not to turn cloudy white even after 10 to 20 years of use.
Techniques
Free-blown glassblowing (chubuki)
A technique in which, without using a mold, molten glass is gathered on a blowpipe, air is blown into it, and the piece is shaped while being rotated in the air. 萩ガラス工房 makes vessels with this technique, and in the hands-on experience a professional craftsperson gives one-on-one instruction. Because the pieces take time to cool, they are finished through steps such as polishing the base.
Uchi-hibi Kannyu glass (inner-crackle glass)
A technique in which glass is built up in three layers and crazing (kannyu, a crackle pattern) is sealed in the middle layer. It encloses inside the glass the kind of crazing that appears in the glaze of Hagi-yaki (Hagi ware); the cracks spread with temperature changes, and the pattern gradually changes. It has excellent heat resistance and strength and is said to be unlikely to break even when boiling water is poured into it.
Materials Used
Production Process
- 1
Preparing the raw material
Quartz basalt collected on Mt. Kasayama is crushed at the studio and made into raw material for glass.
- 2
Melting
The raw material is placed in a furnace and melted at high temperatures of 1,500°C or more.
- 3
Forming
Molten glass is gathered on a blowpipe, and air is blown in to shape it.
- 4
Cooling and finishing
After being cooled slowly over time, the piece is finished by polishing the base and other steps.
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Artisans & Workshops
萩ガラス工房
A studio in Koshigahama, Chinto, Hagi City, that makes Hagi glass. It carries out the entire process in-house, from collecting quartz basalt to melting and making products, and produces basalt glass, Uchi-hibi Kannyu glass, Hagi kiriko (cut) glass and more. It is run by 萩ガラス工房有限会社 and also produces engraved commemorative items and architectural glass.
Official site →How to Buy
- 萩ガラス工房 (shop)
- A shop attached to the studio at 1189-453 Koshigahama, Chinto, Hagi City, selling vessels of basalt glass, Uchi-hibi Kannyu glass and more. Studio tours are free. Open 9:00 to 16:30, every day of the year.Where to buy →PR
- 萩ガラス工房 (online shop)
- A mail-order website run by 萩ガラス工房, where you can order the studio's products.Where to buy →PR
Hands-on Experiences
萩ガラス工房（宙吹きガラス体験）
山口県萩市椿東越ケ浜1189-453
With one-on-one guidance from a professional craftsperson, you make one blown-glass vessel. It takes about 20 minutes, costs about 5,000 yen, and is open to junior high school students and older. Because cooling takes time, the piece can be picked up the next day or later, or shipped (shipping extra). Reservations are by phone only, and the experience may be suspended for melting-furnace inspections and other reasons.
View details →萩ガラス工房（アクセサリー制作・彫刻体験）
山口県萩市椿東越ケ浜1189-453
Accessory making is an experience of working glass with a gas burner; it takes about 45 minutes and costs about 2,000 yen. In the engraving experience, you carve patterns onto a mirror, plate or drinking glass using the sandblasting technique; it takes 1 to 2 hours and costs about 2,500 yen. In both cases you can take your work home on the spot. The engraving experience requires a reservation by the previous day.
View details →FAQ
Q. Is the green color of Hagi glass added coloring?
A. No, it is not added coloring. It is a natural pale green produced by the iron oxide contained in the raw material, quartz basalt.
Q. Is the Bakumatsu-era Hagi Garasu the same as today's Hagi glass?
A. Because the production method had died out, 萩ガラス工房 studied it based on old documents and other sources and revived it by adding modern techniques. The Bakumatsu-era Hagi Garasu is said to have been made from crystal stone from 江船山 in Mine City, while today's Hagi glass uses quartz basalt from Mt. Kasayama as its raw material.