Kanazawa gold leaf is not just a material, but has established itself as one of the traditional crafts representing the craft kingdom of Kanazawa.

The Shibi (bird's tail-shaped ornaments attached to both ends of the tiled roof) of the Great Buddha Hall of Todaiji Temple and the Torige Ryujo Zu Byobu (gold folding screen) in the Shosoin are examples of temple's gold leaf craftwork. It is also an important material used in the production of a variety of cultural assets and works of art, such as Nishijin Ori brocade in Kyoto and Wajima lacquerware in Ishikawa. In recent years, gold leaf has also been used for food and beauty, such as in "gold leaf soft ice cream" covered with gold leaf, "gold leaf facial mask," in which gold leaf is applied directly to the skin, and "gold leaf nails," in which gold leaf is placed as an accent in nail art. In addition, demand for gold leaf has been increasing as one of the materials that enable new creations in architecture and interior design.

Kanazawa gold leaf is a generic term for not only gold leaf, but also silver, tin, brass, and other metal foils. Not only does it show the color of the metal itself, but also by subtle changes in composition, the addition of special processing, and different ways of attaching it to the surface, the freedom of creation is unlimited. Kanazawa gold leaf will continue to play an important role in Japanese crafts while opening up a new history.

It is said that gold leaf was first produced in Kanazawa in 1593, when Lord Maeda Toshiie, the founder of the Kaga domain, received an order from Toyotomi Hideyoshi during the Korean War.In 1808, the burning down of the Ninomaru Palace at Kanazawa Castle was the catalyst for the establishment of the foil industry in Kanazawa. Although a large amount of gold leaf was needed for the revival of the industry, the shogunate at the time placed only Edo foil under the protection of the shogunate, and prohibited the production of other types of foil. Therefore, it is said that the Kaga clan was secretly making foil in craft workshops. Therefore, the technique of gold leaf production was inherited throughout the years.

In 1864, only the official foil of the domain was allowed to be made into foil, and Kanazawa foil made great progress. Furthermore, with the disappearance of Edo foil in the Meiji era (1868-1912), Kanazawa foil could be produced and sold throughout the country as a market.During World War I, Kanazawa foil was mechanized to meet global demand. During World War II, the foil manufacturing industry was temporarily destroyed by restrictions on the use of metals, but production resumed during postwar reconstruction and the uses of gold leaf expanded.

Gold leaf is around 10 - 20 thousandths of a millimeter thin. So thin that only 2g(0.07oz) of gold can be pounded to the size of one tatami mat. So many factors need to be perfect in order to produce the ultimately thin leaf - exceptional craftsmanship, paper production that is known to determine the quality of the finished gold leaf, good climatic conditions and more. 

1. Gold alloy

The first step is to melt gold with minute amount of silver and copper. Silver and copper are blended because 99.99% gold is too soft to be pounded into thin leaf. The mixture is placed in a hearth bowl and heated to about 1300℃ (2372℉) and stirred with a carbon rod. Wait for 10 - 15 minutes to completely melt, and pour into the molds to shape.

2. Rolling out

The gold alloy is rolled out in the pressure roller to a belt-like shape called nobe. Repeat this process for 20 times to make the strip of two - three hundredths of a millimeter thin. Cut into 6cm(2.4in) squares.This square is called the “Koppe”.

3. Preliminary Pounding

The Koppes are pounded into thin leaf of the size of the entire leaf-making paper. When pounded into 12cm(4.7in) squares, the gold is called the “Aragane”, which is then cut into quarters and pounded into the 20cm(7.9in) square. Now, it is called the “Koju”. The “Kojus” are cut into quarters and pounded further to make The “Oju”. When the “Ojus” are placed between finishing paper, they are called the “Uwazumi”.Gold is three thousandths of a millimeter thin at this stage.

The “Uwazumi” of three thousandths of a millimeter thin is finished into the 10 - 20 thousandths of a millimeter thin leaf. The “Uwazaumis” are cut into 12 pieces, which change the name to the “Koma”. In this step, the “Koma” is placed between the rough pounding paper one at a time.

The thin leaves of gold placed between rough pounding papers is fixed with leather and pounded by the metal pounding machine. Once sufficiently thinned, the leaves are transferred to the readied fine pounding paper of “Omogami” and pounded further to the 10 thousandths of a millimeter thin.

Once the gold leaf is finished, each one is transferred to the stack of paper called “Hiromonocho” after the quality inspection. The bamboo tweezers and paper finger sacks that do not cause static are used in this process. Very delicate handiwork is required here as the process involves extremely thin gold leaf of 10 thousandths of a millimeter which can break with the weakest air flow or static.

The edges of the leaves in the Hiromonocho are trimmed in the final process. The finished leaf is then transferred to a stack of a hundred papers for the final assessment. The quality is graded and the finished leaf is temporarily stored in a box until being cut to size.

Gold leaf is sold in four sizes - 10.9cm(4.3in), 12.7cm(5in), 15.8cm(6.2in) and 21.2cm(8.3in) squares. The leaves are trimmed with the cutting frames. The trimmed gold leaf are placed onto specialized Japanese paper called "Kiri Gami", which means cut paper.