The nature and fate of natural resins in the geosphere—IV. Middle and Upper Cretaceous amber from the Taimyr Peninsula, Siberia—evidence for a new form of polylabdanoid of resinite and revision of the classification of Class I resinites

Abstract

Analysis of three amber (resinite) samples collected from Middle and Upper Cretaceous sediments in the Taimyr Peninsula, Siberia, indicates that these materials are based on copolymers of biformene (I) and communol (II). These resinites represent a previously undescribed form of Class I (polylabdanoid) resinite. Definitions of the sub-classes of Class I resinites have been revised (generalized) to recognize the general relation between these samples and other Class Ib resinites, and to facilitate classification of polylabdanoid resinites which do not necessarily incorporate communic (or ozic) acids.