偏光による宝石研究の基礎 : 3

概要

論文の詳細を見る
The basic knowledge on the optical crystallograghy is introduced as a basis of investigation of gemstone. In this part, interference colour produced by crystals which have no birefringence dispersion is mainly discussed. To represent the colour, the well known X Y Z system of the C. I. E. is used. In this chromaticity diagram, the chromatic locus with the increase of the retardation shows behaviour of, in part, ellipse-like line, which runs clockwise around the point of C-light source. Although the discrimination between X'and Z'can generally be done by observing the additive or subtractive colour, using the sensitive colour plate, it is shown that the plate is not so effective when the retardation of the observed crystal section is considerably large. The method for determining the retardation of the section by means of various kinds of compensator is also explained .
宝石学会(日本)の論文
1977-03-15