Tuesday, September 24, 2013

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.

Metal Retreat 2013
Judy Rose demonstrating Keum Boo

Metal Retreat 2013
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.

Metal Retreat 2013
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.

Metal Retreat 2013

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.

Metal Retreat 2013

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.

Metal Retreat 2013

And a little patina made it even more interesting.

Metal Retreat 2013

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!





12 comments :

  1. I didn't get a chance to play with this but I have done a little in the past. It's loads of fun and I plan on doing some next year. Here are the earrings I made which sold long ago. https://www.etsy.com/listing/23964853/yin-yang-fine-silver-and-gold-earrings

    ReplyDelete
  2. I can not wait to see what else you do! This looks awesome!

    ReplyDelete
  3. That looks like a fascinating process and I love your pendant!

    ReplyDelete
  4. Wow this looks very interesting and I might get brave enough to try it.
    Therese

    ReplyDelete
  5. Fascinating, I look forward to more about this technique!

    ReplyDelete
  6. Hi everyone! I'm not sure if this is the place to post, or not, but I've stopped receiving email posts. The last one in my inbox is dated September 22. I look forward to the posts everyday...is there something I need to do to start getting them, again? Thanks in advance...E

    ReplyDelete
    Replies
    1. Hi Eleanor! Yesterday's post was published much later than usual. Perhaps that is why you didn't receive it...wait a day or two and see if you get them. If emails have stopped working, I would have no idea how to fix it except to check your spam folder and maybe sign up again for emails and see if it starts working again.

      Delete
    2. It's there, now! I guess I just "jumped the gun" a little...haha. I enjoy the posts very much...Thanks for sharing (and responding)! E

      Delete
  7. Oh wow - how cool! Beautiful pendant. Looks like a ton of fun was had by all of you!

    ReplyDelete
  8. Thanks for the kind comments, everyone - it really was a lot of fun, and I am STOKED to start playing with this technique!

    ReplyDelete
  9. Oh YES! I love this technique....been wanting to try it. Now that I see how simple it is, all the more so! Thanks for posting and great work!

    ReplyDelete
  10. hi. can this technique be applied to copper?

    ReplyDelete

We would love to hear what you have to say, please leave a comment.