Optical Microscopy is affordable and provides plenty of information for art documentation and examination. Though, my feeling is that it has been overlooked in academia and in education for conservation scientists and probably also for conservators. You don’t want to shoot a mosquito with a cannon, right? A good enough polarizing microscope goes for $5000 (much less on the used market) and it last forever. There has been a bias toward new, fancy and costly instrumentation and Optical Microscopy has been put aside just because it was not fancy enough. In my experience, I was never taught how to use an optical polarizing microscope — nevertheless to take samples and prepare cross-sections. I had to figure out it myself and I really enjoyed reading W. C. McCrone’s papers — a beacon in the field [1, 2]. This thought is shared by others . I really hope that students would be taught on how to use basic, affordable, scientific tools and not just the fancy and expensive ones.
This blog is about cross-sections preparation. They are useful for painting conservation and authentication. Warning! The epoxy resin and the hardener are toxic, you must wear gloves and a mask when handling them. This video should be self explanatory about how to make cross-sections from paintings. I found this resource very useful published on line by Orion Analytical . I’m going to cover other “microscopy and art” topics in the following blogs.
Materials you need (this is just my personal list of materials):
- stereo microscope
- EpoxiCure Epoxy Resin 20–8130-032 Buehler 0.95l
- EpoxiCure Epoxy Hardener 20–8132-008 Buekler (o.24l)
- 8” microcloth PSA 10/PK Buehler 693–3
- 8” Carbimet 2 abrasive paper 600/P1200 Plain back Qty 100 PN: 30–5108-600–102
- 8” Carbimet 2 abrasive paper 400/P800 plain back Buehler PN: 30–5108-400–102
 W. C McCrone (1982) “The Microscopical Identification of Artists’ Pigments” Journal of the International Institute for Conservation—Canadian Group 7 (1–2):11–34.
 W. C McCrone (1994) “Polarized Light Microscopy in Conservation: A Personal Perspective” Journal of the American Institute for Conservation, Vol. 33, No. 2.
 R. Weaver (2003) “Rediscovering Polarized Light Microscopy” American Laboratory, October.
 Orion Analytical, “Preparing layered samples for microscopic examination in cross-section” http://www.orionanalytical.com/Preparingcross-sections.pdf