In addition to the polymer matrix, amber also contains nonpolymerisable
compounds such as low molecular weight organic
acids, monoterpenes, and diterpenes (abietanes and pimaranes). Previously
thought to be free within the macromolecular structure, recent
studies have shown that a portion of the terpenoids are bound to the
polymeric structure in certain ambers (Poulin and Helwig, 2015). The
composition and abundance of these non-polymerisable compounds
varies widely among amber samples – even within samples from the