The Spectroscope and Gemmology

Until 1933, the refractometer and the microscope were the two principal tools in gem testing. Then B.W. Anderson introduced the hand spectroscope which quickly became the third vital instrument for the UK gemmologist. Anderson and his lifelong colleague, Payne, both of the world's first full-time gemmological laboratory, were the pioneers in recognizing the vast potential of the spectroscope, and The Spectroscope and Gemmology is the extensively edited, updated, and enlarged version of Anderson's original papers. The distinguished gemmologist R. Keith Mitchell undertook the editing and added of chapters on the Pye spectrophotometer and on lasers. He also reproduced new line drawings of spectra in three aspects to accommodate the prism instrument in both the British version and in that favored by American gemmologists, and in another version as seen through the diffraction grating instrument.