IR spectra of Burnt umber (Fe2O3+MnO2+clay) mixed with linseed oil
This burnt umber is Sennelier’s product.
ATR-FT-IR spectrum
IR spectrum with ATR-correction
The low wavenumber region (far-IR region) of this IR spectrum is presented and discussed in the following paper: Spectrochimica Acta Part A, 2010, 75, 1061–1072.