Fluorescence Characteristics of Blue Amber from the Dominican Republic

Abstract

GEMS & GEMOLOGY WINTER 2020 Amber is widely distributed around the world. It is of interest not merely as an important natural fossil resin witnessing the history of the earth and providing direct evidence for paleobiologists, but also as a widely loved organic gemstone. Transparent yellow amber from the Dominican Republic, Mexico, and Myanmar displaying a blue or greenish blue glow when viewed on a black background in normal sunlight is called “blue amber” in the Chinese gem trade. This paper focuses on amber displaying this characteristic and will refer to this material as blue amber. In the Guangzhou and Shenzhen amber trading centers, Dominican blue amber can be sold for up to thousands of Chinese RMB (around several hundred U.S. dollars) per gram, while Mexican material fetches only several hundred RMB (around several tens of U.S. dollars) per gram—even though they have a similar appearance. Bellani et al. (2005) first described blue amber and studied the fluorescence emission, excitation, and optical absorption spectra of Dominican blue and non-blue (including yellow and red varieties) amber. They found that multiple emission fluorescence peaks at 449 nm, 476 nm, and 505 nm occurred in this blue amber, while only a broad fluorescence band was observed in non-blue amber. They further