Gemological table calcite dichroscope

Calcite Dichroscope is a regular test instrument which special used to observe the polychroism of gem.In some cases Polychroism is the foundation to judge the gem, especially when the Refractometer, Polariscope and other instruments can't judge the color gem is Homogeneous mass or Heterogeneous body.Calcite Dichroscope is a efficiency tool to judge the optical characteristics of color gems.

FID-1A Features:

Gemological calcite dichroscope

1.With base,excellent iceland spar;

2.Standard rectangle window and square window can be choosed.

3.Rotating stage,gemstone and dichroscope can rotating 360°,

4.Adjustable up and down,backward and forward,easy operation

5.High resolution

6.Black appearance,aviod reflecting interference
 

Basically FID-1A Calcite Dichroscope with stage is a tool that lets you view the different colors of a dichroic piece of rough. It shows whether or not a stone is dichroic (reflects 2 colors). This can be helpful in differentiating stones of the same color from one another. Dichroscopes can be useful with identifying gemstones that are still in the rough and when stones are set and difficult to get to with other instruments. Light entering the dichroscope is broken into two polarized rays that have vibrational directions at right angles to each other. The two images in the dichroscope represent the polarized light and the pleochroic colors signifies doubly refractive stones except if the stone is viewed thru the optic axis. Single color in the dichroscope represents singly refractive stones. There are several different types of Dichroscopes, but the most common type is one made with Calcite. It is used by most people for identifying whether a piece of rough is dichroic.

The advantage of the dichroscope is that the two pleochroic colors that may be characteristic of a given direction in a doubly-refractive gem are seen side by side. If no dichroism is identified in the first assessment, the stone can be turned and viewed in other directions. Trichroic stones like Andalusite will show all three, just two at a time while you rotate the rough, you will see three colors. Trichroic gems can also be distinguish and will reveal three colors if the stone is viewed in three directions perpendicular to each other.

It is an ideal tool for getting a good idea of how the color(s) on a piece of rough are going to look in a finished gemstone.