Micro-chemical methods for mineral determination.

Microchemlcal analysis is one of the many methods used in the chemical examination of minerals. This method requires a petrographic microscope and also a knowledge of optical mineralogy. Since the microchemlcal method requires only a small sample, it is preferable to other methods in determinative mineralogy. The purpose of this paper is to present a description of the characteristic reactions and of the optical properties of the resultant crystalline precipitates of certain common elements. The optical constants are worked out in detail, in so far as the technique used permits. It will be noted that a number of these are not in complete agreement with those given in authoritative tables. An attempt has been made to interpret the interference reactions resulting from the test solution of some complex minerals with the reagents, in the hope that they may prove useful to the detection of cations and, therefore, to the determination of the composition of minerals.[...