Keum–boo is a very old gilding technique, originating in Korea, that is used to apply very thin sheets of 24 karat gold to silver surfaces for decoration in the form of a silver-gilt. It’s very much like a silver leaf.
Traditionally, this technique is accomplished by first depleting a surface of sterling silver to bring up a thin layer of fine silver.
The Keum-Boo workshop, held at The Brewery Arts Centre (Kendal), was a great finish to January.
The course covered the Keum-Boo technique – a stunningly simple, yet incredibly effective addition to any jewellery maker’s repertoire.
The workshop focused on:
- Preparing your silver
- Applying the 24kt gold foil
- Use of colouring agents
Translated into English, Keum-Boo means “attached gold”, and if you haven’t come across the technique before, you are in for a treat!
Above: Students learning depletion guilding techniques at the Brewery Arts Centre in Kendal, Cumbria.
The basic process
It’s an ancient Korean technique where 24 karat gold foil is applied to fine silver as a decorative element. This is to highlight texture, create an image, or enrich a pattern. The foil is applied under heat and burnished to form a diffusion bond between the two metals.
The resulting “two-tone” metal can be enhanced by using a colouring agent to create fabulous contrast. Liver of sulphur is a little whiffy when applying but it gives beautifully warm, rich colours. This can be seen in the featured image for this post.
Who can do it?
Although the techniques can be used by complete novices, this particular group were all experienced hobbyist jewellers. Most of whom I had worked with in previous workshops or classes. Almost all of them brought in pieces that were nearly finished – created elsewhere by them and ready for decoration.
This saved a lot of time as less of the day was spent making individual pieces. Some students preferred to decorate sheet silver to be used as a raw material for later pieces.
With an understanding of the basic technique, and the right equipment, jewellery pieces can be finished relatively quickly.
During the class
Students were encouraged to experiment with the technique over the course of the day:
- varying the amount of depletion gilding
- layering gold foil
- applying foil to curved as well as flat pieces
- using polished and unpolished metal
A fantastic variety of approaches came out of the tumble polisher and everyone had a fantastic time.
More info
You can find out more about Keum-Boo at the ganoskins website. It covers a lot of the technical aspects on how it works.
Using Platinol to add colour gives your piece a stunning contrast. Watch the Platinol in action, how fast it works and the resulting colour.
You can, of course, use Liver of Sulphur too, which gives a variety of colours from straw to purple. This can be seen in the Keum-Boo demo pieces shown in the featured image at the top of the page.