Archaeology isn’t all about digging holes…

Paul Coleman, Project Manager updates us on paint.

It’s about uncovering the past to inform the future.

The scientific approach continues at the Folly where paint research has been undertaken to research and investigate the sequence of decorative colours which may have been used on the outside doors of the building.

What we want to do is try to find out what colours and paint types they used since the building was complete (1772) through to its occupation as the Game Keepers House (1805) up to present day.  We are trying to match the colour of the Game Keepers front door…..

The process is an archaeological investigation and we have employed Karen Morrissey a specialist paint researcher to look in depth at the building, colours and paint used.

The process involved taking bits of the paint which then are taken to the laboratory.  The samples were embedded in polystyrene resin, cut in half and the end polished which gives a cross section through the paint layers.  Using very high powered Microscopes under ultra violet and high power lighting – we are able to see each individual layer of paint.

Looking at the sample at 63x magnification, gives very impressive results.

Magnified cross section of paint layers

Magnified cross section of paint layers

Looking more like layers of cheese on toast or a vegetable lasagne, these images allow us to see the number of paint films, including primers and undercoats.

As well as the microscope work, samples were also sent away for testing to establish the presence of any natural, manmade or other pigments (colours), the type of pigment can be used to aid dating of the paint layer.

So, what have we found…..

Sample number 2

Ground floor door frame

 

The frame of the ground floor door is more interesting than the basement door – looking at the paint coatings to the timber and counting them, there are 13 schemes applied. The paints are generally stone and buff coloured lead oil paints; however there is one scheme of ‘invisible’ green and also one of very dark grey/ black early in the paint strata (schemes 2 and 3 respectively). These paints may be ‘impenetrable’ paints, which were manufactured from coal tar.

On one of the samples it shows that the oak timber frame appears weathered, suggesting that the timber may not have been painted originally or that its early coatings failed to protect the timber that well.

From the photographic evidence we can see circa 1880 that the doors were painted in a two tone colour (obviously in black and white in the photo !!!!) but gives an indication of the tonal difference which may be desired.

Problems can be experienced in paint analysis with such things as paint loss on the surface, weathering, deterioration of materials, colour fading and loss and as with the Folly there is evidence that some of the timber to the basement has been stripped with a blow torch.

Door

Ground floor door

 

Folly

Gamekeepers door showing the two tone effect

The basement door is less interesting as there are only 3 paint layers,  with indication that the door has previously been stripped of all its paint.  However the Microscope images are much more dramatic…..

amber layer

The amber layer is the softwood frame

There is now the debate as to which of the 13 colours we should opt for –  so come along during the Summer to see if you like the Game Keepers front door.

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