Polariscope Guide, Part 3: Testing For Gemstone Twinning, Dichroism, and Crystal Strain

Step 3: Practical Gemology

Lesson 14

gemstone twinning - polariscope guide
Gemstone twinning

A gemologist can conduct many different tests with a polariscope. Gemstone twinning, dichroism, and internal crystal strain are some of the physical and optical characteristics that can be studied through this instrument.

Gemstone Twinning

A crystal doesn’t always form in a single step. If one of the required elements for a crystal’s growth is depleted, it will stop growing. When the proper mix of ingredients is present again, growth will resume. Some crystals will continue to grow as a whole, without any division. Others will grow in layers, one on top of the other. This is known as …

Premium Article

This is a Premium Article. Please become a member to read this entire article and gain access to hundreds more like it.

Membership options