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Carbon-13 nuclear magnetic resonance (NMR) with cross polarization and magic-angle spinning (CP/MAS) Is applied to whole and processed lodgepole pine wood to Investigate the relative amounts of and interactions between the major constituents. Grinding the wood has no effect on the 13C spectrum, but ball milling converts "crystalline" cellulose to the amorphous form. Extraction with dimethyl sulfoxide or steam enriches the residue with "crystalline" cellulose. Five different lignin preparations yield fractions with distinct 13C NMR spectra. Various preparations of holocellulose, hemlcellulose,

The carbon‐13 NMR spectra of amber from several mining sites in the Dominican Republic show considerable variation. In certain cases the differences are sufficiently distinct to serve as a reliable indicator of provenance. The gradations within the resonances of unsaturated carbons may reflect the relative ages of the samples, because fossilization and diagenesis can remove this functionality.

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