Gold Leaf
Production Process

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 melting pot is heated to 1,300 Centigrade and gold, silver and copper are added.
Wait for 10 - 15 minutes to completely melt, and pour into the molds to shape.

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

The Koppes are pounded into thin leaf of the size of the entire leaf-making paper. When pounded into 12cm squares, the gold is called the “Aragane”, which is then cut into quarters and pounded into the 20cm 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.

[Paper Production] The grass paper placed between leaves and pounded together is the essential tool for gold leaf production. It is so important that the quality of this paper determines the quality of the finished gold leaf. It is the grass paper soaked in water with eggs, persimmon tannin and ash to add resistance to impact.

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. Gold leaf is sold in four sizes - 10.9cm, 12.7cm, 15.8cm and 21.2cm squares. The leaves are trimmed with the cutting frames. Holding the leather-covered woodblock in the left hand, the craftsman transfers the gold leaf from the “Hiromonocho” with bamboo tweezers. The transferred gold leaf is press-trimmed by the frame. The trimmed leaf is placed over the “Kirigami” paper to finish.