Traditional Kintsugi : Finishing Your Repair with Gold Powder

When you think of kintsugi, you most likely think of traditional potteries with gold lines all over their surfaces. It makes sense since kintsugi literally means "gold joinery." In traditional kintsugi, which is based on the use of urushi lacquer, genuine gold powder is used to obtain a gold finish. However, did you know that there are actually different types of gold powders that can be used for the finishing layer ?

Today, we will present several types of gold powders and techniques that you can use for the finishing layer when repairing a piece of ceramic with traditional kintsugi.

Different Types of Gold Powder

You have put broken pieces together, filled chips and made all the restored parts water resistant with black urushi: you can now proceed to applying the finishing layer ! In traditional kintsugi, the finishing layer usually consist of gold powder dusted over fresh red urushi. Red urushi is applied once the undercoat of black urushi has fully hardened.

Gold powder can be classified into 3 types of gold powder: keshi-fun (消粉), maru-fun (丸粉), and nobe-fun (延粉), also called hiragoku-fun (平極粉). This classification relates to differences in shape and size.

In addition, gold powders are also commonly categorized depending on their level of purity. The purest type of gold is referred to as 24kt gold. At Tsugu Tsugu, we used 23 kt gold.

1. Keshi-fun (消粉)

Keshi-fun presents the smallest particles of gold of all. They are thin and have a paper-like shape. It’s said that  keshi-fun is made by squashing 1 g of gold and then breaking it into fine 0.3μ-thin gold leaves.

2. Maru-fun (丸粉)

Maru-fun presents the largest gold particles. They are spherical. Maru-fun is made by filing bare metal and scrubbing it into tiny balls. Each gold particle has a diameter of about 5μ (0.005mm) to 0.3mm. The powder is categorized into 17 stages per its size. The size 1, with a diameter of 6μ, is the smallest size and the size 17, with a diameter of 0.3 mm, is the largest size.

3. Nobe-fun (延粉), also called Hiragoku-fun (平極粉)

Nobe-fun is a gold powder that stands halfway between keshi-fun and maru-fun. Its particles have an oval shape and a thickness of around 6μ.

Ease of Use

For Beginners : Keshi-fun

We usually recommend beginners to use keshifun because it is easy to handle and requires very few touch-ups. Many artisans also like using keshi-fun because it is usually cheaper than other types of gold powder.

We usually apply keshi-fun on the thinly painted urushi with silk ball.

For Advanced Learners : Maru-fun

Thanks to its thicker particles, Maru-fun adds an even stronger shine to objects repaired with kintsugi. However, it is trickier to apply and it usually requires a lot more touch-ups compared to keshi-fun and nobe-fun. Special material such as a powder-filtering-tube (called Fun-zu-tsu 粉筒) are also needed for its application. For all these reasons, we usually only use maru-fun with students that already have a solid experience with kintsugi.

Maru-fun is the most expensive type of gold powder and, nowadays, it is getting harder to purchase maru-fun because the number of people doing kintsugi has incredibly risen over the last few years. In late 2020, we were told by some of our gold suppliers that they couldn’t keep up with the demand. We had to wait for several months before we could receive our order of maru-fun.

For intermediate learners: Nobe-fun

Nobe-fun requires more steps than keshi-fun but fewer than maru-fun. Price wise, it is more expensive than keshi-fun, but cheaper than maru-fun. When nobe-fun is used as finishing powder, it is usually applied using “Tai-ki”, a stick with a tooth of porgy (a kind of fish) on top, to polish the gold finish.

Differences in Appearance

All kinds of gold powder shine beautifully, but there are some distinct differences.

In our workshop, we also use keshi-fun with students that are still starting to learn kintsugi repair. With keshi-fun, the finishing layer has a matt and bright appearance. The end result depends on the class of keshi-fun you choose (Class 1 : lighter, Class 4 : darker).

In contrast, a finishing layer with maru-fun usually looks like burnished gold, with a nice glow. It is really beautiful to look at but, with maru-fun, you really need to get the groundwork right before applying the finishing layer. If the lower layers have not been perfectly applied and smoothened, the maru-fun layer will appear all wrinkled, and this will not look pretty at all. Maru-fun should only be used after having got fully used to kintsugi repair techniques.

When it comes to nobe-fun, once again, it stands right between keshi-fun and maru-fun.

Differences in Durability

Since maru-fun presents larger gold particles, it tends to resist friction better compared to the two other types of gold powder.

Nobe-fun is not as resistant as maru-fun, but it is stronger than keshi-fun.

It is also worth noting that gold finishing layers usually resist rust much better compared to other metallic finishing layers such as silver, brass or tin.

No matter which type of gold powder you choose, you should always treat all objects repaired with kintsugi as lacquered items. In other words, you should always make sure to wash them gently by hand and avoid scrubbing on the restored parts.

In Conclusion

As we have covered in this article, picking a gold powder to dust on the scars of an object repaired with kintsugi is not as simple as it may seem.

When picking a finishing powder, you base your choice on three things:

1. Your experience with kintsugi (beginner vs advanced learner)

2. How you will use the object after repair (food safe vs not food safe)

3. The finish you seek for your project (metallic vs natural, matt vs glossy, bright vs darker)

If you are a beginner and are looking to get started with kintsugi, the safest strategy is to go for keshi-fun. This type of gold powder is easier to apply, and this is why it is the type of gold powder we have decided to include in our kintsugi kit TSUGUKIT.

If you have already completed several repairs with keshi-fun, you may want to challenge yourself and give nobe-fun or maru-fun a go. If you ever need any advice, you can always book an online class. We will be more than glad to help.

In this article, we focused on the gold finishing layer, but there are a lot of other options such as plain urushi, pigmented urushi, or other metallic powders such as brass, silver, platinum, etc. Be aware that some finishing powders, such as brass, are not certified as food safe.

When you think of kintsugi, the image of gold lines is most likely the one that sticks the most in your mind. However, it is very important to stress that the gold finish can only look good if the groundwork has been done right, and it is especially true when using maru-fun.

So, take your time, focus on each step of the repair and, when the time comes, pick the finishing techniques that suit you the most in your kintsugi project and journey !