DARKER (aka LEESON) TYPE OF ROTATING SELENITE STAGE

c. made from about 1880 through at least 1945)

BY: Negretti & Zambra (?)

Serial number: none

This 'Selenite Stage' provides a deep well which rotates via a pinion controlled by a knurled knob. The supplied selenites can be dropped into the cell, either individually or in combinations, and can be oriented in several different directions from each other to impart different effects. This device reveals a wide variation in colors of polarized objects-a very entertaining accessory. The selenites have the effect of changing the coloration of objects seen under crossed polarizers. The degree of the effect varies with the type of object being studied, and different colors are imparted by different selenites. In use by the author, this device seems to offer a wider variety of variations than the 'Mica-Selenite Stage'. This one comes with a lacquered brass can containing two selenites in brass rings, and two in plain glass. The can has a fancy engraving as shown in the image. This example of a selenite stage is thicker than some other examples. The example by Watson on this site is thinner, and the selenites are encased in black rings rather than the lacquered brass rings with the example on this page.