CSA 7-R, 5¢ blue vertical pair, 4 margins, tied neat bold CHARLESTON S.C. NOV 17 cds on fresh cover to “Rev Prof J M. Schreckluse, Newberry CH, SC”, part of back flap slightly reduced otherwise Extremely Fine. $180.
High-surfactant stamps comprise only 11% of CSA 7-R stamps (Richmond prints) tested by Dr. Harry Brittain with FTIR. Dr. Brittain is a chemist, philatelist, and award-winning author. This appears to be a bit of an anomaly. Surfactants (surface active agents) can be broadly defined as compounds which, when dissolved in water, concentrate at surfaces such as water-air, or water-oil. The interfacial activity of these substances, which can be explained in terms of their molecular structure, gives rise to a wide range of surface chemistry functions: wetting, emulsifying, lubricity, and more. Fourier Transform Infrared Spectroscopy (FTIR) is a technique used to obtain an infrared spectrum of absorption, emission, photoconductivity, or Raman scattering of a solid, liquid, or gas. An FTIR spectrometer simultaneously collects high spectral resolution data over a wide spectral range.
Click on image to enlarge.
