Sunday, 7 August 2016

Creating an Antique Finish

In this blog I would like to explore the challenges of re-creating an antique gilded frame. To describe a frame as antique is not only to recognise the style of manufacture but to see also the effect of age on the surface of the gilding. This effect we call the patina and it is in the reproduction of that patina that presents the greatest challenge to any framemaker.

                                          Frame - Richard Christie Antique Frames
 
A first question is why we would put such a value on this patina. After all, when the artworks were first completed and a new frame chosen, the idea of a patina was hardly considered. So, what is happening here and why do antique paintings look so correct when framed in an antique frame?



Well, even with careful restoration and sensitive cleaning, antique paintings still have an appearance of age. The oils and varnishes will  have oxidized and many of the pigments reacted with the atmosphere to now give a subtle tone that we recognize as a signal of age. So too with the original frame.
And if we look closely at an antique frame we will see what appears to be a crust on the surface of the gilding and it is the colour and texure of this finish that matches so well the patina evident on an antique painting.




It would now be interesting to examine what might be the make-up of this crusty patina.
Let us imagine a large gilded frame, newly comissioned and hung up in a grand 18th century house. It probably houses a family portrait or some old master bought  during a grand tour. We shall assume it is a Rococco or similar style frame with the high points on the ornaments burnished and the contrasting matt areas muted back with some weak size.




The gilding will be bright and soft toned and serve well to illuminate the artwork in daylight. At night the frame will sparkle and shimmer in candlelight.
Now, after several hundred years, the frame still looks splendid but it's colour and character will have radically changed. The gold will have turned dark green in places, will have been worn through on others and along the bottom will have a rather heavy deposit of dust clinging on to the surface. And the unusual thing here is that that deposit of what appears to be loose dust is in fact quite a durable and permanent finish.




So is this the white dust we see when we run our finger over the top of a  wardrobe? Well yes but it isn't coloured white. That is just the appearance of scattered light off the surface.This  dust will have been made up of soot from candles, ash from open-fires, fibres from clothing, earth particles carried in on clothing and foot-ware, insect debris and most common, skin flakes and hair from the household occupants.
So all this stuff will have been floating about in the room and have settled onto our gilded frame. But instead of getting blown off, the moisture and hydrocarbons in the air condensed onto the dust to form perhaps an oily compound. These hydrocarbons would be from candles, oil lamps and even tobacco smoking. And then along comes the house-cleaner and wipes "clean" the surface of the "dusty" frame. What they have really done is smeared a thin coat of this compound all around the frame. This was repeated over many years and so built up a paint layer of patina. As this paint layer got thicker, so the light reflected off the gold and through this compound, became more subdued and altered to so represent the colour we see on antique frames today.


                                Photo - Richard Christie

Of course this patina became a more and more durable  from the slow oxidation of the hydrocarbons polished into it's surface.
Another interesting thought is to compare the patina on Italian frames with those of North European origin. The Italian frames tend to be lighter toned but have a more heavily crusted patina. Perhaps this was because there would have been fewer hydrocrbons loose in the air; in other words a warmer and brighter climate so less need for heating and lighting. And did the Italians then not need to clean their frames as vigorously as their Northern European neighbours?



To complete the examination of the patina now visible on our frame, we must mention all the small chips, scratches, dents and losses to the gilding. These are of course a result of years of handling, polishing and cleaning. A psychiatrist would describe all these as perceived visual complexity. We are always happy to see this on a frame as it confirms authenticity of it's age and supports the antique aesthetic we value on old frames.



Having explored the origin of the patina on an antique frame, the next challenge is how to reproduce it on a newly gilded surface.
Re-creating the visual complexity mentioned above is a simple matter of knocking and scratching the outer edges of the frame. Next will come the distressing by abrasion where the gilding is partly worn through in places, to the underlying gesso and bole. If all this is done with care and subtlety, then the gold will remain bright and glistening for the next stages.


                     Frame - Richard Christie Antique Frames
To make a paint that will mimic the patina we will need two elements; a mix of pigments to supply body colour and texture, and a binding medium to blend and fix them to the gilded surface. As we have discussed, the main components of the patina are natural products such as dust and organic debris. The pigments that represent these colours of nature are the earth pigments; deep shades of red, brown and yellow. If we wanted to just give a hint of age to our frame, then it would be perfectly adequate to paint on a light glaze of selected earth pigments.


                                Photo - Richard Christie

The glaze however that I have created has been the result of many hours of trial and experiment. Behind all the mixing of pigments has been the belief that too many colours can often result in an opaque mud, so every trial was subject to as much editing of the pigments as possible.
The basis of creating an aged effect was to use some of the earth pigments. These are the colours of nature but used alone can be very singular in their effect. In fact many of the earth pigments, if used too predominantly, can be heavy, lifeless and dull. So after selecting a suitable earth hue, several other pigments were added to sharpen up their colour. These were then given definition by adding in a further group of pigments.
Now if we look closely at the finish on an antique frame, especially where it is heavily patinated, we can see that the crust has an almost granular structure, rather like fine sand. And even with this heavy coating of material, the gilding beneath remains bright and reflective.


                                       Photo and Frame - Richard Christie
 
So the mixture of earth pigments must be modified to create this reflective quality and also added to a base that gives the impression of a crystalline film and not just a dull powdery finish.
And to top it all, the whole mixture is given accent and colour by the addition of a selected group of dyes.
I can liken this to a musical chord where the series of notes all work in harmony and even one note out of place can corrupt the whole sound, so with this mixture and all it's ingredients - just one incorrect pigment or dye can distract and deaden the overall effect on the gilding.  

The glaze that I have now created, when applied skillfully and with a matching degree of distressing, will well mimic the colour and patina found on many antique frames. The glaze is waterbased and and can be overlaid in several thin coatings. The finish can also be manipulated for subtle stippling effects and easily removed again, if worked in error.
To purchase or enquire about this glaze, please contact me at

dermotmcardle12@gmail.com


 Sample corner water-gilded with 231/2 ct gold.


The same corner, distressed and painted with several coats of Ageing Glaze.