We have a sign that we did about 2 years ago on the beachside. It was gilded with 23K gold but not clear coated.
It is starting to show what seems to be tarnishing (I figure that it isn't). Could it be a salt buildup on the sign and can it be cleaned?
Thanks......
[ September 14, 2006, 01:36 PM: Message edited by: Nevman ]
Posted by W. R. Pickett (Member # 3842) on :
...Does it ever get sprayed by lawn sprinklers? I've seen some signs down there that went orange from the sulfer (or something) in the water. Otherwise, gold is impervious to the elements.
Posted by Nevman (Member # 332) on :
Thanks...you may be right. Didn't think about that. I'll check that...
Posted by bill riedel (Member # 607) on :
Years ago I had that happen to a sign done with 22kt.
Posted by goddinfla (Member # 1502) on :
Saw a story in one of the sign mags years ago by Dusty Yaxley about this happening. I believe it was due to sprinklers and pollution. If the gold was made with copper it turned red, if made with silver it turned blue. These are added to make any carat less than 24.
Posted by Jean Shimp (Member # 198) on :
I would agree that it's the other elements in the gold composition that are tarnishing. The sign doesn't seem to have any water staining on it or other evidence of sprinkler issues. I swithched to 23.75k gold and to be honest the gold brilliance did get dull after a couple of years and minor tarnishing occurs. The only time I use gold leaf is on a carved or dimensional letter where the added dimension of the letter reflects the gold. I often hear people say that gold lasts a long time but here in Florida by the sea it changes after a couple of years.
Posted by Monte Jumper (Member # 1106) on :
Gold does not tarnish!
A discoloration can occur from skin oil by being touched (when applied or after the fact) oxidation can occur from the substraight it's on and be washed away with cotton and a mild solution of water and vinegar.(Be careful)
Best thing at this point would probably be to clean it resize it and regild.
But 22 23 0r 24 karat gold "does not tarnish" anything you are seeing is from an outside source and will likely continue. Varnishing will only flake off and creat bigger problems.
Posted by Monte Jumper (Member # 1106) on :
I just re-looked at your picture.
I'm not questioning your ability to read product label...but is it possible you had some "Dutch Metal" laying around and got it by mistake? It would stay brilliant for a year or two then turn exactly the way your picture shows.
Dutch Metal looks and acts just like gold but is heavier (like varigated gold) both of which actually have no gold in them what so ever.
In which case it would patina just from the moisture in the air.
What size were the sheets of leaf?
Posted by Stephen Deveau (Member # 1305) on :
There is something you are not telling us! Gold never turns!
Posted by Nevman (Member # 332) on :
Monte...it's true 23k - Sepp Leaf Crocodile Brand is all we use. It even says so on the lable...
I think that Goddard and Pickett got it right. The wells that we have down here that are used for irrigation are full of sulfer.
Haven't had a chance to get back to the sign yet (it's about 1/2 hour away and we are replacing one of the names anyway so we will be back down there soon). I'm going to try to clean the gold - not totally sure how yet - and I'll let y'all know how it turns out.
Posted by Amy Brown (Member # 1963) on :
I agree with Jean. Why would only the gold turn color if it was the sprinklers? The whole sign would turn orange.
Don't have any other solution but I really don't think it's sprinklers.
Posted by Nevman (Member # 332) on :
That's a good point Amy...to be fair, I haven't seen the sign personally - our installer took the pics. He did say that there seems to be some sort of residue on the sign face as well.
I will keep you posted.
Posted by Monte Jumper (Member # 1106) on :
Well...you're not going to be out anything so why not take the chance...
"Limeaway" a spot. If it works use cotton and and rinse with clear water.
I've done this on letters with water spotted calcium deposits...(never on gold tho) good luck.
Posted by Jeff Ogden (Member # 3184) on :
Pat...
Here is my theory. Hold a sheet of 23k gold up to the light. You will see an uneven , almost blotchy appearance, with some areas much lighter than others.
When you put gold on a surface, you are adhering an extremely thin layer of gold to sizing. This gold has some areas that are so thin light penetrates it, as you can see from holding a sheet up to the light.
So two things are happening when the gold is exposed to the elements. One, light is penetrating onto the size, in whatever small amount. Secondly, air, moisture, contaminants, all are also able to penetrate, on a microscopic level, through the gold and on to the size.
This all contributes to the size itself oxidizing, turning a darker color as the pigments fail, then losing it's gloss, causing the gold to lose it's adherence to the size.
The result is what appears to be tarnished gold, and is in reality, what's left of the size. Everyone assumes that because gold is pure, that it will also protect the size under it from the elements, and I disagree with that assessment.
Using double gold may help the longevity of uncleared gold, but the elements are eventually going to win, and the size will begin to fail. When any paint does fail, it slowly turns to dust. somewhere in that process, the gold will come off.
Posted by Monte Jumper (Member # 1106) on :
Jeff ...I like that therory! But how would you explain the gold leaf on a capital dome lasting so long, years in fact.
Anyway...I hope Nev gets back to us and lets us know what the real explanation is.
Please do that Nev?
Posted by Tony Vickio (Member # 2265) on :
I was called last week to look at a sign that someone else did and the letters looked exactly like this one! I rubbed my finger on a letter and a brownish, powdery residue was on my finger. This is NOT Gold Leaf, I told here. She showed me the invoice and the sign was sold as Gold Leaf. I can't believe this Dentist sign is 23K Surface Gold! Real Gold is Gold! It won't and can't tarnish!
Posted by Nevman (Member # 332) on :
I assure you Tony...it's real gold. I know it's not tarnished but there is some sort of surface contamination going on.
Like I said earlier, we will be going down to install the new name next week and I will have more info then...promise.
Posted by Jeff Ogden (Member # 3184) on :
Monte...
My guess is that capital domes, church steeples, etc., as well as many other locations are cleaner, less polluted, than anything at ground level, where you have car exhaust and many other pollutants to contend with. These pollutants mix with rainwater to form a toxic mix that eventually gets to the size, causing it to fail, and the gold to become "unglued".
In Pat's case, my guess is that it is 10x's worse when you have salt mixing with sulpher water, which is naturally acidic, and who knows what kind of nastiness that will produce. Sulpher lowers ph levels and is used in agriculture to correct high ph.
Or so the theory goes....again, it's unproven speculation at best, but I feel like the gold is not tarnishing, but rather the size under it is failing because of extreme conditions, because the gold layer is so thin, that it is allowing moisture and light to penetrate to the sizing. When the size deglosses and gets powdery, the gold comes off.
[ September 19, 2006, 01:13 PM: Message edited by: Jeff Ogden ]
Posted by Monte Jumper (Member # 1106) on :
Well...I'll be glad to hear the outcome on this one!
Posted by Ron Percell (Member # 399) on :
Surface contamination with brass & gold, 24kt least likely to tarnish being pure. The brown stain looks like water & sun damage.
Most gold leaf contains percentages of Silver and Copper.
It could also have some Salt & Sand blasting (from storms) It looks to be wearing evenly.
Was the Gold Size Contaminated with an Oil Based Paint?
Size should only be tinted with pure pigments suited for oil or water based products.
For best results use the slowest sizes available, paint the surface with imatation gold enamel(no metallics, too pourous)prior to sizing the surface.
Coastal Evironments can be very harsh on gilded surfaces, we experience alot of storm damage here near the Pacific North Coast.
I'd gild it again and let the client know that if it occurs again, that it should be gilded & clear coated next time with 3 coats of clear & that 2 trip charges will be charge.
If the client chooses to have you clear coat it this time around, then you will at least break even for your troubles.
Gilding it again will show good faith on your part, and the sign will run out it's expected life span before needing regular maintenance.
Good Luck
Posted by Chuck Peterson (Member # 70) on :
Its hard to tell from a photo but could it be that the gold has come off, exposing something darker under a clear size? This could happen if it was gilded too late after the size was dry.
Posted by Cam Bortz (Member # 55) on :
I seem to recall that Rick had a problem like this and traced it to contaminates in sprinkler water. I've done lots of signs with lots of leaf literally within yards of salt water, and have never seen this happen - which causes me to doubt that salt air or salt water is the culprit. And like everyone else, I'm waiting for the results of further investigation.
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