Amber of different color and fluorescence has recently been found in a lignite seam in
the Zerkal'nenskaya depression, Primorsky Krai, Russia. In this deposit, the amber is
associated with abundant charcoal and fusain fragments in the host rocks. Beside
three composite samples of different color from the lignite and one composite amber
sample from the Sakhalin Island has been included in this study for comparison.
Based on previous fluorescence and fluorescence excitation measurements, the
blue glow of amber has been related to the fluorescent aromatic hydrocarbon
perylene, although FTIR study of the Russian blue amber has not found any distinct
signature of this compound. The present analyses using gas chromatography-mass
spectrometry have also identified no perylene in any of the four Russian amber
samples. The hydrocarbon fractions of the extractable organic matter from the
ambers are dominated by C18 to C20 diterpenoids of the labdane, abietane,pimarane,
phyllocladane and kaurane types. Their biomarker composition is consistent with the
proposed origin from gymnosperms of the families Pinaceae, Cupressaceae, and/or
Taxodiacceae. The cause for the blue amber glow could not be clarified based on the
commonly used methods of hydrocarbon composition study.