Inferior glass gold

An interactive section of TheLetterheads.com

Topics include: Sign Making, Design, Fabrication, Letterheads, Sign Books.

Off Topic Posts may be deleted at the discretion of the web hosts. ABSOLUTELY NO SHARING OF COPYRIGHTED FONTS, CLIP ART, or VIDEOS!

Please take social chit-chat elsewhere!

Moderators: Danny Baronian, Mike Jackson

Post Reply
Robert Schwieger
Posts: 120
Joined: Wed Feb 07, 2007 12:38 pm
Location: Nebraska

Inferior glass gold

Post by Robert Schwieger » Mon Jul 02, 2018 11:20 am

Recently purchased Glass Gold - 3 1/8x 3 1/8 - Made in Germany. In sampling this against current glass gold I noticed an obvious difference primarily a slight "mottled" effect. Cpmparisons were made using the same procedure, cleaning prep, sizing, gelatin, application, backup and cleaning excess. Is this due to environmental contamination such as humidity, chemicals, etc. ? This might work on surface gilding such as picture frames but it cannot be acceptable for glass gilding. This quality will not pass the client's approval. Ideas? Thank you. Bob.

Lee Littlewood
Posts: 219
Joined: Thu Apr 15, 2004 2:36 pm
Location: Portland, Oregon
Contact:

Re: Inferior glass gold

Post by Lee Littlewood » Wed Jul 04, 2018 1:11 am

Yup.
There is always grousing about how things were better in the ‘good old days’, but I think that with the change to machine beating instead of hand beating the character of gold leaf rally has changed. Or maybe the good is as good or better than before, but the bad is worse.
Last year I was involved in a re-gild project: the job was only 8 years old and the (surface) gold was pitting and mottling, often showing dark edges along the leaf edges. The solution was to strip down to the bare metal, reprime, repaint, resize and regild. But this gold was made for us by a Thai beater (“Golden Leaf” - a representative is close to us in Vancouver Washington), it was meant to be 24k and we know its provenance. Whether it lasts well in the salt air, the smog, the chlorine spray from a fountain and the general fog of Los Angeles remains to be seen.
BUT in researching the gold problem we came across an article by Chinese metallurgists, analyzing corrosion in “traditional gold leaf”. They found that yes, gold could corrode in moist air with sulfur and nitrogen compounds; that the copper in the leaf was a corrosion center; and that the gold itself was corroding. This they thought came from the thinning process (it didn’t say if it was hand or machine made leaf) which produced micro-deformation areas that allowed corrosion. What we are hoping is that if the beaters anneal the gold as they work it, there will not be so many micro-deformations. But if annealing is an extra cost who will do it?
I hear that Chinese gold leaf is actually common - it is made in China but sold under different names. So my takeaway is to be careful about where I buy my leaf, ask them who produced it, and be wary of ‘great deals’. All “Duh”, but it’s all I got.
Gold Leaf corrosion article 0 copy.jpg
Gold Leaf corrosion article 0 copy.jpg (554.37 KiB) Viewed 220 times
where am i? Now, when i need me...

Post Reply

Who is online

Users browsing this forum: No registered users and 5 guests