Monday, December 17, 2007

Single Gilding vs. Double Gilding

An object that is double gilded has two layers of gold leaf laid, one atop of the other. This is normally done with the traditional water gilding process and imparts a very deep, golden tone that is generally free from defects in the gilding. Water gilded leaf has a satin tone in its natural state; burnishing the gold or silver leaf brings the metal to a brilliant lustre.

When water gilded leaf is left satin, it's left un-burnished. This means that the leaf not only has a satin tone but is also not compressed against the wooden object, such as a picture frame, and therefore bonding of the leaf to the gessoed wood is somewhat more vulnerable to wear. It has historically always been this way and old gilded frames and furniture that has unburnished satin areas will likely show more wear than its burnished counterparts. Therefore, I often use additional RSG (glue) in the gilding water to aid in adhesion and sometimes apply a 5:1 RSG:Water wash over the satin leaf for added protection.

Single layer gilding usually results in some anomalies ('spots' exposing underlying clay bole from pin holes; air holes or breaks in the leaf) during the process of water gilding, many of which can be covered during spot gilding, although if done excessively the result can be unsightly. Double gilding covers all the anomalies that single gilding sometimes leaves behind and is useful when gilding satin areas. It offers a very solid layer of gold leaf.


There are times, though, that the somewhat translucent quality of single gilding is preferred when developing a satin section, especially when other areas of the gilded object are rubbed, abraded, or distressed. As an example, a picture frame that is antiqued to some degree can be somewhat jarring if the sides are a strong solid double gild. It is often aesthetically best if the overall appearance of the gilding presents a sympathetic quality between each of the sections, where no one area is dramatically different in its condition.

18 comments:

Ian Russell said...

Charles, I found this article very interesting and I'm inspired to give double gilding a try especially on frames for modern pictures where the unrubbed no-fault finish might suit. One practical question; I assume the first gilding is cleaned up so that the second gilding doesn't bind to unattached leaf but do you burnish the first gilded layer. Also I wonder for no other reason than keeping costs down whether it would be possible to second water gild real gold over a metal leaf first gilding either oil or water gilded. As ever I would be interested to read your thoughts. Regards. Ian.

Charles Douglas said...

Thank you Ian. These are good questions, the same I asked many years ago. How you treat the double gilding and burnishing comes down in part to how you want the gilded object to look. Your entire concept should actually be considered before you even begin the gilding process. Before you even begin laying the gesso since every step in the water gilding method affects the outcome, so you need to know in advance what you want to achieve before you start applying materials; otherwise, the approach you take with your materials like gesso and bole may not serve the design you develop later in the process.

That said, I suggest burnishing your first gilding layer before applying a double gild. Re-wetting the surface can sometimes cause the leaf to pick up. Use a little glue in your gilding water, like 1 gram to a half a pint of distilled water and no alcohol.

Burnishing not only makes the gold shine, it compresses the leaf into the surface, so this way the burnished leaf is more durable than the unburnished areas.. However, if you want a satine-toned double gilded surface, then do not burnish either the first or second gild. Just be careful in laying the leaf.

As far as real gold over metal leaf, well, I'm all for exploring new ideas and techniques so try it if you'd like and see what happens. That's the best teacher. But remember, gold is very malleable which is why it works so well with water gilding. I saw a frame on a Miro in Spain once that had water gilded brass leaf (metal leaf) and so I tried it. It'll work but water gilding is really meant for gold or silver. Plus, water gilding isn't the finish to use if someone doesn't have the money for it. It's either done with gold or use the brass leaf and oil gild that if money is an issue.

Hope that helps!

Melissa Jones said...

I am new with gilding. When you say single vs double in this article...do oyu just mean you are going to do it twice? I'm looking at LA Gold Leaf and they sell a 24k gold single and a 24k gold double leaf. I want to do outdoor large 3D letters. Do oyu think I should buy the double or single? Thank you for any help!

Charles Douglas said...

Hi, Yes, when I say double gilding I mean gilding an object twice, which I refer to for in traditional water gilding, something I sometimes do for various reasons such as effect. The outdoor letters you describe would be oil gilded, a different process using one application.

Single gold and double gold is different than single or double gilding. This reference by the sellers of gold leaf refer to the thickness of the gold. Double thick isn't really double but it is thicker and I would recommend that because the heavier the leaf the greater it can withstand the effects of the environment (wind, dirt, etc.). A top coat is not necessary as the gold will last longer than any chemical that might be applied. The only time I would suggest doing so would be if it is subject to handling.

Hope this helps!

phantomfive said...

Good information, thanks, I was wondering if it was possible.

Charles Douglas said...

You're welcome. Yes, many things are possible; just need to know what the options are and that can take a while to learn. I teach workshops and put out a newsletter so that can give people a leg up so to speak.

geoff peach said...

gilding articles are always interesting. I have been gilding for many years and once a single layer of leaf has been applied and is dry, I always make up a tepid weak gelatine solution and apply the gelatine with cotton wool to the gilded area. Once dry, the second layer of gold is applied an always takes beautifully. Once dry, it always burnishes extremely well. I would usually double gild if I was say, gilding a swept carved frame where faults etc from a first gild are easily covered.

Davis said...

Coming in very late to this I wonder if you could offer some advice to me?

Though I have been water gilding relatively successfully for many years, the current project is not going well. I use the Thompson Method but in this case the leaf has not adhered to the bole well in fact hardly at all. If I were to use a "liquor" with some gelatin in it (Thompson doesn't suggest it), might that work?

I'd be happy to double gild if needed.

I am desperate!

thanks

Davis

Charles Douglas said...

Hi I found the Thompson method didn't work well either when I tried it out some years ago. It sounds like your glue strength of the bole may simply be too week. If you already have the bole laid down then I suggest adding a little more glue to the gilding water than you may have already. Adding alcohol won't help with the adhesion.

Otherwise, remove the bole and try this:
20 parts 10% RSG or Gelatin
10 Parts Distilled Water
37 Parts Bole that has been thinned to where it's like milk

Good luck!

Davis said...

Thanks so much for your quick response!

Yes I think that was the problem - the bole was a bit think as I recall - I'll try adding glue to the gilding liquid (I've never done that) and see how it goes. Many thanks!

I am especially grateful as it has been 2 years since I water gilded and I have a large project to do soon - this smaller piece is a good re-training.

Davis said...

Sorry to be a bother. If I add gelatin to the gilding water how much in proportion ought that be? (I have never added glue of any kind to the water only water & alcohol as Thompson recommends.)

Many Thanks,

Davis

Elisabeth Caron said...

Hello Charles and Davis,

Regarding gold leaf not adhering to bole properly, and making a mess, it may be that the ambient air is too dry for the amount of alcohol in the liquor (the liquor evaporates too fast to wet the bole).

I had a frustrating morning yesterday trying to water gild a frame, until I realized my mouth and nostrils were parched (the heat had fiercely kicked in overnight in my building but, too eager to gild and then too busy being frustrated, I had not noticed).

I boiled pans of water this morning before I started patching up yesterday's shoddy work...and the leaf is adhering beautifully.

I will double gild the frame to hide the imperfections. I knew that was possible but I had no idea how to proceed. I googled "double gilding" and there it was. Charles, thank you for your indications--i.e., your dedication and generosity.

caroline said...

Hi

I understand you are referring to water gilding here, but is there any reason you should not double gild when using the oil gilding process? And if so, is it a simple case of applying the oil based size over the first layer of gold?

I am looking to gild an outdoor object that will potentially get both close scrutiny and some wear.

Thanks

Charles Douglas said...

Hi Caroline, There is no reason why you shouldn't be able to double gild your oil gilding project. Yes, just oil size right over the first layer after it has dried sufficiently. However, that said, if the first gild was done properly you shouldn't need to double gild when oil gilding, a single layer is sufficient.

For exterior work, choose the heaviest weight leaf you can find (look for the grams per pack description in the catalog or ask your supplier). This will help lengthen the life of your gilding outdoors. No varnish is needed as the gold will last longer than any varnish you might apply. Use a slow dry size if you can.

Good luck and thanks for writing!

Charles Douglas said...

Elisabeth, Thank you for your reply about adding moisture to the room when gilding. Very interesting! I always moisten my bole several times before leafing, making sure the thin layer of water remains on top. The first couple of passes has the water flowing right into the gesso.

Browning Lui said...

Hi Charles, in a beginner about water gliding. Recently I did a white gold polish on a piece of maple wood flat surface.

I did 8 coats of Gesso, n 5 coats of boles. I let it dries about 4 to 5 hrs n I began to polishing. However, I couldn't get to a good clean finish. Am I missing some steps there? I glided the surface twice with a 13k white gold.

There is another question. Y people tend to use 12k white gold or 22k gold instead of 13k white gold, or 24k gold? Is that the reason y I can't create a nice clean finish? Please help.

Thank you, it's awesome to find this blog, with lots of knowledge behind gliding. I love gliding because it's fascinating. : )

Charles Douglas said...

Hi Browning, Water gilding needs to be seen as a system with all of the different parts working together to achieve a particular result. The very first step which you didn't mention is the application of a layer of a 10% rabbit skin glue solution to seal the wood before applying gesso.

When you say "polish" I assume you mean burnish, the term for compressing the gold into the surface with a burnisher, usually made of agate, making the gold shine. The number of gesso coats you are applying should be enough to give you a fairly decent, smooth burnish although I generally use 14 coats of gesso along with 5 coats of bole. However, a good burnish depends in part upon the recipes you are using for the gesso and bole which include the strength of the glue and the ratio between the amount of glue to whiting (calcium carbonate) for the gesso and the ratio between the glue and bole, the addition of water and the viscosity of the clay itself. All of these factors, among a few others, contribute to how the gilding will appear.

If you can provide me with further details on how you approached your project and the gesso and bole recipes you used we can take a further look into what's happening.

As for why gilders tend to use 12k or 22k rather than 13k or 24k, good question! There are probably a lot of different answers to this. My view is that 22k is still high enough in gold content to appear as 'gold' without shifting too far into a different tonal spectrum. Also, the silver content makes 22k perhaps easier and quicker to handle which may be important for companies geared towards high productivity and is also less expensive than 23k. I use 23k though over 22k because I find it is a little more malleable and wraps around ornamentation a littler more effectively.

12kt, being essentially 50/50 gold to silver, strikes a nice balance between the malleability of gold without overtaking the look of silver. 24kt, meanwhile, has a beautiful, deep rich gold appearance although it is very soft and may not be practical on a daily basis for an industry such as picture framing if productivity is an issue. It may, however, be the first choice for Sacred Works due to 24kt's purity and therefore spiritual symbolism. A high gold content leaf such as 23.75k is desirable for exterior work as gold does not tarnish. When gold leaf tarnishes it's the silver or copper content within the lower kt leaf that is tarnishing, not the gold.

These different karat leafs, however, do get used and offer an interesting array of color choices to compliment works of art and may also be useful in color-matching in restoration, conservation, reproductions, and replicas. I don't think the karat leaf you have chosen though is necessarily contributing to the difficulties you have had in achieving a smooth, burnished appearance.

Browning Lui said...

Thank you so much Charles, that's very informative.

Its true, I didn't put rabbit skin glue on my wood before I laid my gesso.

I put 60% of whiting gesso powder, and 40% of rabbit skin glue into mixture. The rabbit skin glue that I had was bought in some art supplies shop. its not the flakes rabbit skin glue that people normally use I guess. I warm my rabbit glue, and put 60% of gesso in it and start stirring until its done. I filter it and start spraying the gesso on my wood. I sand between coats.

last week I realized if I burnishing the white gold longer, I'll have a much mirror like effect on my gold. So, I am wondering is that I have to keep burnishing the white gold until it turns mirror like finish?

I also have difficulties to judge when I should burnish my gold. some time I feels that if I let it dry over night, and burnish it the next day. my gold don't seems to breaks apart easily than burnishing in a 5 to 6 hours time frames because I keep breaking my gold if I burnish it about 4 to 5 hours time frame.

thank you for your help

Browning