Keum BOO!

Well, I'm just back from our very first Metal Retreat, which I co-hosted with my friend and fellow metal artist Melissa Muir. We had sooooooo much fun - we played with new techniques and equipment from one another's studios and laughed our fool heads off. (You can read more about the trip on my blog if you'd like.)

One of the techniques I played with was Keum Boo. It can be pronounced either "kim boo" or "kum boo", and it refers to the process of applying precious metal foils to other metals.

E. Christopher & Sons Keum Boo Pendant

Silver Keum Boo Bangle by Jewelscurnow on Etsy

Fire Pendant #2 - Keum Boo by Robin Cruz McGee

The idea is that by adding thin foil layers to a piece, it's possible to get the effect of precious metal for a lower cost and without casting or laminating different metals together. (Charles Lewton-Brain has a good summary article of the particulars over on Ganoskin if you're interested in the science of it.)

One of the attendees at our retreat does a lot of Keum Boo - and we were all fascinated.

Judy Rose demonstrating Keum Boo

A pair of Judy's Keum Boo earrings. Photo by Morgan Corder Bass.

So I took a stab at it. And I'm in love.

Start by depletion gilding your sterling silver piece so that it is covered in a thin layer of fine silver. Depletion gilding is accomplished by repeatedly heating and pickling the piece until it stays white or pale grey when it's heated.

Depletion gilded pieces (made from my scrap pile)

Then the pieces are put on a hot surface - we were using a table top beehive kiln, but in my research a hot plate with a piece of brass on the top supposedly also works. I'll be testing that theory - the hot plate is much (MUCH) less expensive than the beehive kiln.


When the piece gets up to temperature (between 500 and 700 degrees) the 24k gold foil "relaxes" down onto the silver. That's when you can start burnishing the foil down.


You can use either a steel burnisher or an agate burnisher, but be aware that if the steel burnisher gets too hot, the gold will fuse itself to the burnisher instead of the piece. Use a small container of water to keep the burnisher cool - but don't quench the agate burnisher, or it will crack! I used one of each - one to hold the piece steady while I burnished with the other.

The result was pretty cool.


And a little patina made it even more interesting.


The gold foil seems a little pricey at first - $80 to $90 at current prices for a 3-1/2 inch by 3-1/2 inch square. But trust me, a little goes a long way. I am completely in love with the potential of this technique and I plan to be doing a whole lot more of it. And since it seems you can also foil other metals, I'll be experimenting with those too - silver foil on copper or brass? Gold on aluminum or steel? Lots and lots of possibilities! Stayed tuned!

How about you? Have you ever tried Keum Boo? Ever tried a technique that just grabbed you and wouldn't let you go?

Until next time!