Getting Started

After getting settled back in to campus and reacclimating to the Williamsburg weather, our lab hit the ground running.  The first two weeks were a flurry of planning, reading, organizing and ordering supplies.  After concluding the semester with a letter (short article) published about our findings in the fleshtones of paintings by Robert Feke and Sir Joshua Reynolds, we knew there was still many more tests that need to be performed in order to prove that our techniques of pigment identification with Surface Enhanced Raman Spectroscopy (SERS) and correllated flourescence is practical and widely applicable for use in the art conservation community. 

Two of the things that we emphasized in the published letter were the value of SERS in identifying tricky organic pigments and the ability to learn something about the pigments’ environment (i.e. what binders, varnishes, resins, etc. are present)  using the correllated flourescence.  For both Reynolds and Feke we determined that the carmine lake pigments were likely mixed in linseed oil.  In addition, we concluded that,  Reynolds was likely using some other material, possibly copal, as a varnish.  With these results in mind, we knew that the next step was to probe the effectiveness of this method for other types of pigments and binders.  We determined that we should test two series of historic reference paints,  one series of the same pigment mixed in a variety of binding media and another where the binding media was held constant and the pigment was changed. 

Some of you may be wondering where on earth we were going to get all of these paints from, they certainly dont come ready-made from a store!  Last Thursday,  I had the unique and awesome opportunity to spend the day in Williamsburg’s Paintings Conservation Lab with our collaborator Shelly Svoboda as she showed me how to “grind” these paints that we would be using in our tests.  The process involved measuring out raw pigments onto a large marble slab and slowly adding the binding media as you ground up and mixed the two together until everything formed an homogeneous mixture.  Usually this grinding process would be done with some sort of mortar and pestle, but our experiments require a high degree of cleanliness (cross contamination could confuse results, especially working with such small samples) so we traded in the traditional mortar and pestel for the marble and glass rods which could be more easily and effectively cleaned between batches.  All in all we produced 20 different paint samples to test.  Ill definitely have plenty to do as soon as all of them dry! 

Throughout the process Shelly was very careful to photographically document everything we used to produce these paints and was kind enough to take a few pictures on my own camera during the process.  I figured Id post them here for you all to see as well so you would know that Im working hard and simultaneously having a blast with this project!

Photos courtesy of the Colonial Williamsburg Foundation.