News from Colourman: The World of Mythical Colour

"A short time ago the artistic world discovered that on garden gates, farm fences, etc., there was a most lovely blue-green colour to be seen sometimes. This was Brunswick green in a state of dilapidation, and was showing that it needed re-painting. However, the colour was so lovely that many attempts were made to copy it in new paint. They all failed hopelessly. One cannot with paint fake the work of time".

Brunswick Green
These words of Basil Ionides, written in the 1930s, came to mind when Patrick Baty was talking to the owner of a large country house in Norfolk. Papers and Paints had been requested to devise a good blue colour such as (we were told) "had always been used on the gates and doors around the estate".

It doesn’t really matter, of course, that the blue that our client had in mind had almost certainly been a dark green when originally applied, for age had changed both the colour and the finish to produce a very pleasing result. A few years earlier, Basil Ionides had been more specific:

"Brunswick green outside is delightful after about three years, when it begins to become a lovely verdigris colour, but one has to suffer a dull colour till then, and this change really means that the old paint is perishing and new is needed."

Several years ago we were commissioned to investigate the exterior paint colour in the National Trust's famous Hidcote Manor Garden. For the last forty years the well-known bluish green has been used, however analysis has shown how this was a misinterpretation of the earlier Brunswick green. Perhaps surprisingly the original colour appears to have been brown.

Although modern paint no longer 'chalks' as an old lead paint does when it ages the colour still wanders. This can be seen on a south-facing green-painted front door after a few years. When opened, the edges which have been protected by the frame are noticeably greener and darker than the door itself.

Brunswick green 'on the turn' – the colour becoming noticeably bluer and paler.
NB also the flaking that is characteristic of an aged modern paint
In recent years blue seems to have become a popular colour for such surfaces even though it was seldom used on external woodwork in the past. Another colour with which it is confused is the one frequently referred to as the generic “French Chateau Shutter Blue” (could it be that there is more than one?) by several customers who have heard of our range of paint colours based on some of those seen across the various regions of France.

A door in the Île de Ré. Acknowledgement Lucy Inglis.
Even when aware of this phenomenon one often needs convincing. Whilst carrying out the analysis of the paint on the estate buildings at Culzean Castle, in Ayrshire, a red-brown door to the Kitchen Garden was seen to display an earlier scheme of greenish-blue.

However, when the paint layers were examined under the microscope it became quite clear that the ‘blue’ was a result of the curious effect of ‘flooding’. This is when one of the pigments in the paint migrates to the surface – in the case of Brunswick green (composed of Prussian blue and chrome yellow) it is invariably the blue that rises as can be seen here:

A thin blue crust can be seen (marked by blue dots) where the overlying red-brown has already flaked off. However where the red-brown is scraped off the underlying paint shows green.

Here is another example recently encountered on a set of Soane-designed outbuildings in Northamptonshire. A slideshow of these buildings can be seen here. A cross section taken from this door is shown below (note how the upper face is bluer than the rest of the layer:

Here is a piece of boarding from the stables at Penrice Castle, in Gower, which shows the colour in its weathered and unweathered form:

Here are some doors in the stable block at Penrice Castle:

There are many myths that have arisen in the world of paint and colour. A number of these will be addressed in subsequent blog posts.

Patrick Baty