[Fwd: Fwd: Re: [medieval-leather] Composite gold leaf]
- Shelly, Tim passed this on to me since I've done a fair bit of gilding
leather. Assuming this is an SCA list, then my quick and dirty answer
is: I wrote an article about this very subject and published in the TI.
It is a cursory article, but mentions most of my attempts, sucesses and
failures in gilding leather. The article was 1989 or 1990, or
thereabouts. I don't have the exact citation on hand. And I'm a little
too busy this week to go digging. Sorry.
Quick and dirty thoughts:
for unburnished quick cold gilding, use gum ammoniac. The leaf,
depending on where the abbrasion spots are, will last between 1 to 10
years. Use "double thick" loose leaf gold.
Hot work: use the method for hotworking described in Heather Child's
(editor) Calligraphers Handbook (2nd ed.). Can't give you an isbn or
page number, since I lent my copy out and it has never returned :(
Edith Diehl (_Bookbinding_) is the best historical documentation in
Engish I've seen thus far (Dover Books). The BEST documentation is in
German, by Gunther Gall, the director of the Leder Museum in Offenbach.
The good news is: this a beautiful technique and the leaf lasts years
(none of my pieces show anything but minor cracking since I made them 6
years ago). The bad news: I had to make my own tools. These need to be
brass or bronze or some other "pot metal." Iron gets too hot and is too
hard to control. The leaf needs no burninshing: frying it into glaire
with the hot tool leaves it "self-burnished" so to say
Composite leaf? Can you say: copper tannates? The real thing just
isn't that damn expensive, from my no-longer-a-starving-grad-student
perspective. Gold reacts with very few other elements, which is why it
gets used so much in certain scientific equipment and on all my scrolls
and leather projects.
Sealing the leaf??? I've never done that. If I were to do that, I
think I'd use period turpentine (the real thing, not the spirits of
turpentine sold in that hardware store). But I've never seen any
mention of sealing leaf on leather, even in Gall. If you really want to
paint or varnish your leaf, some painting sources recommend a thin,
transparent coat of verdigris be applied first. It does make a
difference - I used it on the leaf on a wood panel painting I did, and
the gouache did not bead up like it usually does. I haven't worked out
the chem on this.
> I had planned on using gum ammoniac buta day
>discovered as I started the leafing that it had to be mixed up at least
>in advance & I didn't have the time to wait.Shortcut method of making gum ammoniac
Mortar and pestle: 15 minutes
cooking: glass jar with ground gum ammoniac and water in microwave for
10 minutes. Watch this carefully - you may have to lower the power
setting in the event of violent boiling which can break or knock over
the jar. Use nothing except a glass jar.
straining: 5 minutes
Let it get cool before using
the brush you use with gum ammoniac will probably have to be chucked -
clean up is extremely difficult
you can't burnish leaf on gum ammoniac on leather
this is all the time I can spare right now on ansering questions on
leather gilding - deadline on friday and all that...
ttfn, Therasia von Tux
Tim Bray wrote:
> Don't know if you read the medieval leather list. You might be able to
> answer these people's questions about gold leafing on leather. This
> started out as a question about "composite gold" leaf turning green, which
> of course it will do since it's brass and leather is very acidic, as a
> couple of others have already pointed out.