Why are the trees blue?

Hello Everyone!

Over the past few weeks I have been working towards perfecting a procedure to simulate surface enhanced Raman spectroscopy of an organic yellow art sample.  Many organic yellow dyes produce beautiful SERS spectra with the traditional procedure, involving the coating of a minute sample with centrifuged silver nanoparticles and shooting a laser beam directly onto the particle.  However, lake pigments involve the mordanting of a dye with an inorganic binding medium, making it difficult for the silver nanoparticles to interact properly with the surface of the dye molecules and produce accurate spectra.

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And It Was All Yellow

Hello again!

Over the past few weeks I have spent most of my time familiarizing myself with different types of yellow dyes and pigments, learning about historic methods of paint making and sifting through the chemistry behind organic yellows.  I can safely say I will never look at the color yellow the same way again.  Despite the hours spent separating minute samples of these colorants, I find the engagement with color to be a fascinating and enriching process.  After a background survey to determine the yellows most likely to appear in 18th century colonial oil paintings, I set out to establish a sort of database of comparative SERS spectra from known reference yellows.

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