Keum Boo

All, I just read several posts in the messages about Keum-Boo. It
seems to be a problem to bring the frosted fine silver look to the
surface after Keum-booing. Instead of the traditional pickling
solution (Sparex, …), Felicity from Australia recommends using
commercial grade alum. I do not know what grade alum is and where I
can buy it. Does someone has experience in pickling keum-booed pieces
and where would I be able to find grade alum? Thank you and best, Will

Will, I think I see part of your problem in your post.

    All, I just read several posts in the messages about Keum-Boo.
It seems to be a problem to bring the frosted fine silver look to
the surface after Keum-booing. 

As I understand the Keum Boo process, you should be depletion
gilding your silver BEFORE applying the gold foil. Once you’ve done
that, the frosted silver look will stay through the fusing of the
gold and through the subsequent pickling with no problem. You do
need to use a fresh batch of pickle for best results. When you take
the piece out of the pickle, you’re going to wash it by hand (NOT
brass brush), by the way.

We just did a bunch of keum boo demos last night and it worked
beautifully this way.

Hope this helps,
Karen Goeller
@Karen_Goeller
http://www.nolimitations.com
Handcrafted and Unique Artisan Jewelry

1 Like
As I understand the Keum Boo process, you should be depletion
gilding your silver BEFORE applying the gold foil. 

Hi Karen, Yes, I know :-). Do you have any idea how resistant to
wear the gold is? I just realized that I didn’t see too many
Keum-Booed rings around - could the reason be rather low resistance
to wear?

Best regards and thanks,
Will

Normaly 24k is very resistant to wear. Historical studies have shown
that 24k wears better than anything else, that lower carats (like 18,
14, 10K) abrade while 24k just gets mushed around. That means you
can’t keep a 24k surface intact but you can expect it to weigh well
near what it started out at years later unlike most alloys. best
Charles

Charles Lewton-Brain/Brain Press Box 1624, Ste M, Calgary, Alberta,
T2P 2L7, Canada Tel: 403-263-3955 Fax: 403-283-9053 Email:
@Charles_Lewton-Brai1

Our Collaborative site to benefit the worlds’ jewelers:
http://ganoksin.com/ Over 500 pages of Charles’ writing:
Learning Center - Ganoksin Jewelry Making Community Book and Video
descriptions:http://www.ganoksin.com/kosana/brain/brain.htm
Gallery page at: http://www.ganoksin.com/brain/gallery.htm

1 Like
    Hi Karen, Yes, I know :-). Do you have any idea how resistant
to wear the gold is? I just realized that I didn't see too many
Keum-Booed rings around - could the reason be rather low
resistance to wear? 

Will, the keum-boo foil is approx. thickness of tooling foil, or
about 36 ga. Think of it as 24 kt. thick plating. It will eventually
wear away, but it will take many years of abrasion. If used in a
ring or bracelet, which is normally subjected to a lot of abrasion,
little “guard rails” need to be added to the edges to protect both
the silver design and the gold keum-boo.

I have never tried keum boo on rings, but have used it often on
bracelets and it seems to wear very well. I roll out my own to
about 36 gauge ca n’t get it any thinner with my rolling mill. This
gauge is a bit heavier tha n the kind I got from Komelia Okim when
I took her workshop, but it wo rks just fine. I have tossed it in
the tumbler with steel shot, and brushed it gently with a brass
brush to reduce the glare, and the gold has held up just fine. I
wear one of the bracelets most of the time. This little tidbit may
amuse some of you.,. but the first time I tried to roll out the 24K
piece of gold, I got it down to 36 gauge and thought I could get it
thinner. Nothing worked. I tried sandwiching it between all kinds
of paper and only succeeded in tearing the paper. Tried the o ld
copper trick just got thinner copper,and the gold still remained at
36 gauge. Then I decided to roll two pieces of the 36 gauge
together, thinking they would reduce in thickness. Ha, All that
happened is tha t they fused together totally, so it was back to
reducing the now thickened piece. it had cracks, and air bubbles,
but to my delight they all healed , after repeated rolling, and the
bubbles worked their way out, after being pierced with a sharp needle
and then rolled again… Just adding this little bit of information
in case any one is interested in what happens w hen two pieces of 36
gauge gold are run together thru the mill. Alma, in
still sunny Portland, Or. where the roses are still blooming.

1 Like