Resins, fossilized spectra

Unfortunately, fossil resins are largely insoluble because of their polymeric character, and a dissolved sample is a prerequisite for a well resolved NMR spectrum. We have therefore carried out comparative NMR studies on the soluble pyrolysates of amber and of pine resins. 

The chemical nature of amber is complex. Amber consists of complex mixtures of sesquiterpenoids, diterpenoids, and triterpenoids that have undergone polymerization and molecular reorganization during fossilization. Phenolic units may also be present. Baltic coast deposits, which contain about 8% succinic acid, are often called succinite. Amber is amorphous, and its infrared spectrum closely resembles those of nonvolatile resins from extinct pine trees. It is believed not to be a high polymer, the resinous state being accounted for by the complexity of materials present. Amber also serves as a repository for a variety of extinct species of insects. 

Figure 3. The C spectrum of fossilized resin from Aurora, North Carolina, with normal (lower) and interrupted decoupling.

FT Raman spectrum of fossilized amber resin bead. Conditions as in Fig. 1 except 2000 scans accumulated and wavenumber range 50-3400 cm . ... 

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