About Glasswork
硝子を用いた伝統工芸技法としての「吹きガラス」、「切子（カットガラス）」、「グラヴィール」、「パート・ド・ヴェール」、「エナメル絵付け」をご紹介します。
What is Glasswork? |
Glasswork is made by melting raw material called silica sand in a high-temperature kiln to form shapes and carve patterns. The raw material for glass is finely crushed mineral silica sand, similar to that used in ceramics. It is mixed with lime and soda, then melted in a kiln at over 1200 degrees to become a liquid. Colored glass is made by adding metal oxides and melting them in separate kilns for each color.
The characteristics of glass include its transparent beauty that allows light to pass through and the ability to shape it freely. Depending on the shape and thickness of the glass, its transparency and light refraction can be beautifully displayed. The color changes created by combining colored glass are also noteworthy.
| Techniques |
【Blown Glass】
Molten glass in a high-temperature kiln is wound around the end of a stainless steel pipe (called a rod), and then blown into to inflate it like a balloon to shape it. After forming the shape, it is slowly cooled in an annealing kiln to complete it. Glass made by taking advantage of the shape blown by breath is called "chūbuki (free blowing)," and you can freely create shapes depending on how you blow and move the pipe. Additionally, glass blown into wooden or metal molds is called "katabuki (mold blowing)," which allows for the mass production of identical shapes.
〈Making Process of Blown Glass〉
①Gather molten glass from the kiln onto the rod
②Blow into the rod to inflate and shape the glass
③Rotate and widen the glass with scissors
④Shape it with a paddle and slowly cool it in the annealing kiln
【Kiriko (glass faceting)】
Using a rotating grinder equipped with various shapes of grindstones or diamond wheels, geometric patterns or curves are carved into the surface of the shaped glass vessel. The patterns are refined with finer grindstones and polished to finish. Edo Kiriko and Satsuma Kiriko are well-known examples. The brilliance of light produced by the cut patterns carved at various angles and shapes, and the changing reflection and refraction of light, are the highlights.
【Gravure (copper wheel engraved glass)】
Using a small grinder with a copper plate attached, rotate it while applying an abrasive mixed with oil and sand to engrave patterns on the surface of the shaped glass vessel. You can freely carve designs such as plants and animals. The nature of the glass that allows light to pass through reveals a beautifully three-dimensional relief.
【Pâte de verre】
Pâte de verre (French, “glass paste”), in this technique, artists create the shape of the artwork with clay, then make a mold with plaster. They mix the raw glass powder with a special glue, place it into the plaster mold, and fire it. The glass melts with heat to form the shape of the mold. After slowly cooling, remove it from the mold to complete the piece. The entire glass contains fine air bubbles, making it semi-transparent and giving it a unique pale color.
〈Making Process of Pâte de Verre〉
①Shape the artwork with clay
②Make a mold with plaster
③Remove the clay, place glass grains into the mold, and fire it in an electric furnace
④Cool it, then remove it from the mold to complete
【Enameled glass】
In this technique, artists draw patterns on the surface of the shaped glass vessel with enamel paint. They fire it in an electric furnace at a low temperature of about 600 degrees. The enamel surface becomes glossy when fired.
＜Source: "What is Traditional Kōgei? ”Edited by Japan Kōgei Association East Japan Branch / Published by Unsodo, P.60~63>
