Gold Leaf is produced mostly in Kanazawa prefecture, where is well-known as a traditional art crafts city.
In the Edo period (1603-1867), cultural recommendation policy by successive lords of Kaga Domain refined techniques of craftsmen, which developed the basis of gold leaf manufacturing techniques in Kanazawa as one of the traditional cultures with unique aesthetic sense.
Still now, gold leaf manufacturing techniques in Kanazawa has been succeeded. Around Higashi-chayagai, Kanazawa, many tourists across the world visit the stores dealing with gold leaf.
The elegance of gold leaf casually decorated on daily commodities, attracts a lot of people.
In addition, the delicate decorations of gold leaf can be seen on many cultural buildings and art works representing Japan.
Japanese gold leaf has been preserved by high techniques of craftsmen in Kanazawa and the climate and natural features of Kanazawa, which is suitable for foil manufacturing.
Japanese gold leaf is produced through overwhelmingly long manufacturing process.
Each gold leaf has been produced with careful techniques of craftsmen and the climate with fair humidity in Kanazawa, which has been preserved as Japanese traditional art crafts even today.
The History of Gold Leaf Manufacturing
It has not yet been clarified when the techniques of gold leaf manufacturing were introduced to Japan.
However, looking back the history, in the Tumulus period (300-), jewelry with gold leaf was excavated, and you see gold leaf used on the statue of Buddha at Horyuji temple built in the Asuka period (700-).
The techniques of gold leaf manufacturing were introduced to Japan with the spread of Buddhism culture.
Over the Heian to Azuchi-momoyama period (794-1600), the techniques of gold leaf manufacturing developed gradually.
In the Edo period (1600-), the shogunate established “Hakuza”※1 to control manufacturing of gold and silver leaf.
※1 Hakuza: Control administration of gold and silver leaf that the shogunate established in 1696 to control manufacturing and distribution of gold and silver leaf in Japan
However, in the Meiji period (1868-1912), Edo-haku (gold leaf produced in Edo) died out.
Instead of it, Kanazawa-haku, which was produced in Kanazawa, got on the rise.
Back in the Azuchi-momoyama period (1573-), in 1593, Toshiie Maeda supported manufacturing of gold and silver leaf, which was the beginning of the gold leaf manufacturing history in Kanazawa.
In Kanazawa, there was the culture that cherished traditional art crafts and environment to develop gold leaf manufacturing.
In the Edo period(1603-1867), Kanazawa experienced strict regulation on gold leaf manufacturing.
In Nihonbashi, Tokyo, the Hakuza is operated even today.
However, after Edo-haku died out, the culture of gold leaf manufacturing in Kanazawa succeeded to the next.
During the war, there was the difficult time for gold leaf manufacturing, but it survived over that era to keep producing. Today, approximately 99% of gold leaf in Japan is manufactured in Kanazawa.
Gold leaf has been spread and popular in various ways from traditional art crafts to daily commodities.
Craftsmanship and Humidity of Kanazawa make 1/10,000 mm Japanese Gold Leaf happen
The Edo period was unfortunate for foil craftsmen under regulation on gold leaf manufacturing in Kanazawa.
However, under the control by the shogunate in the strict time, foil craftsman developed their techniques and devices to manufacture gold leaf secretly with limited materials.
Under the strict regulation, foil craftsmen in Kanazawa were tough enough to preserve foil manufacturing, which developed the high level of foil manufacturing techniques.
In Kanazawa, it rains a lot, which brought the saying “Never forget your umbrella, but your lunchbox.”
The humid climate of Kanazawa was suitable to prepare Hakuuchi-shi※2 for gold leaf manufacturing.
※2 Hakuuchi-shi: Paper to finish gold leaf to 0.0001-0.0002mm thick after beating and extending “Zumi”, which refers to 0.003mm thick gold.
The high-level techniques of foil craftsmen and humid environment of Kanazawa has preserved the distinctive quality of beautiful gold leaf in Japan.
Gold leaf manufacturing techniques of Kanazawa is the very world-class skill, which make gold with the half weight of 10-yen coin (about 2g) stretch to the size of one tatami mat (about 1.62 sq.m).
17 processes of Gold Leaf manufacturing
Gold leaf manufacturing processes can be divided mainly into two.
The processes of “Zumi” are 8, and “Haku” are 9, which makes the total of 17.
We will introduce each of 17 processes.
“Uwazumi (the processed gold)“ Craftsmen’s Work / 8 Processes (Zumi process)
1. Gold alloy: Gold leaf is produced not only from gold.
First, gold, small amounts of silver and bronze are put into the heated melting pot.
Then, after they have melted, the liquid metal is poured into a mold to cool down and formed “gold alloy”, which is the basis of gold leaf.
2. Gold stretching: The alloy is placed into a rolling machine to stretch into a belt-like shape.
At this stage, gold becomes 1/50mm thick.
3-8. Zumi-uchi (Beating and stretching):
The following 6 steps are called “Zumi-uchi (beating and stretching)”.
Each name refers to the size of gold on processing.
Stretched gold is placed between “Hakuuchi-shi” to stretch more thinly by beating repeatedly by a machine.
The Japanese paper (Hakuuchi-shi) is essential to produce gold leaf, which is put between foils on beating.
The finishing of this paper can decide the quality of gold leaf itself.
To create “Hakuuchi-shi”, the Japanese paper are soaked in the liquid made from burnt eggs, bitter persimmons and ashes to increase the strength not to tear on beating.
The process of cutting stretched gold into 1/4 size to beat and stretch by machine again is repeated on “Zumiuchi”.
Throughout the processes, gold becomes 1/1000mm, which is called as Uwazumi.
It is as thin as aluminum foil and uneven.
Gold Leaf Craftsmen’s Work / 9 Processes (Foil process)
1. Zumi-kiri (Cutting): Cutting Uwazumi, which is uneven thick, into 9-12 pieces
The thickness differs from the position, so Uwazumi is cut to align it.
2. Shikire (Inserting paper): Placing cut Uwazumi into Hakuuchi-shi.
3. Komauchi (Beating): Beating wrapped binds of prepared Hakuuchi-shi in leather, repeatedly by machine.
After beating, it gets heated, so it is cooled down before beating again.
The stretched Uwazumi to about 10cm square size on this process, is called as “Koma”.
4. Watashi-shigoto (Pulling in): Placing “Koma” between Hakuuchi-shi.
5. Hinoma-sagyo (Warming): Removing humidity by warming the binds of Hakuuchi-shi.
6. Uchi-mae (Before beating): Checking the stretch of foil releasing the binds of Hakuuchi-shi.
After checking, “Koma” is stretched by beating and cooling repeatedly.
7. Nuki-shigoto (Removing): Removing the finished gold leaf from Hakuuchi-shi.
Each sheet is moved to a Hiromono-cho (a pad).
8. Haku-utsushi (Moving foil): Moving gold leaf to leather board to cut into suquares.
After cutting, each leaf is placed onto Hakuai-shi (cut paper).
9. Gold leaf: After all the processes, gold leaf is complete.
At this stage, gold leaf becomes 1/10000mm thick.
The Climate of Kanazawa, suitable for Gold Leaf
The humid climate of Kanazawa has supported craftsmen’s techniques hugely.
Gold leaf easily causes static electricity.
Dryness makes it worse, which means gold leaf needs high humidity.
Also the paper for stretching gold requires fair moistures. The climate of Kanazawa can meet that condition.
By the way, the fibers of the surface of the paper used on beating gold, are crushed finely by being beaten for millions of times as gold by machine.
Indeed, this paper has high absorption force of oil, which makes it work as oil-blotting paper for Geisha’s (a woman entertaining guest on banquets) touch-up.
Preserved Gold Leaf in Japan
Japanese gold leaf is used not only for the limited decorations, but for daily commodities, traditional art crafts and historical buildings.
You can find many daily-use products with gold leaf on sale in Higashi-chayagai, Kanazawa.
Various products decorated with gold leaf are popular there such as chopsticks, tea bowls, fans, cosmetics, necklaces, smartphone cases and so on.
For example, you can buy soft serve topped with a whole sheet of gold leaf, which is very photogenic on SNS.
Gold leaf has many benefits as below.
- Improve barrier function of skin
- Have bactericidal action
- Promote blood circulation
- Promote metabolism
You can eat gold leaf on your meals.
Japanese gold leaf is not only for the selected people, but for everybody’s lives.
This gold leaf culture has been sustained by preserving and delicate spirits and skills of Japanese craftsmen, and the rich history and natural features of Japan.