opal

The demand for the next new thing defines the Modern Age. However, this expectation of significant developments in rapid succession is a recent…

Diamond is the hardest natural material in the world. However, it’s also brittle. Scientifically speaking, hardness measures the ability…

The optical properties of minerals attract our eyes and can give a specimen a unique character. However, mineral physical properties are also…

Although gemstone magnetism isn’t a commonly tested gemstone property, it may be useful for making quick separations outside the lab. By Richard…

In this article, we will discuss phyllosilicates and tectosilicates. These silicate subclasses include minerals crucial for technology and…

Structure Crystal axes and Angles Optic Character Refractive Indexes Optic Sign Pleochroism Examples Amorphous No orderNo axes IsotropicSingly…

In crystallography, mineral habits refer to the way crystals form within a specific mineral. In A Guide to Gem Classification, I mentioned that,…

Crystallography is the study of the formation and structure of crystalline solids. Mineralogists deal with many crystalline minerals and use…

Adamantine. Silky. Greasy? Gemologists and mineralogists use these and other evocative terms to describe luster. This simply means how the surface…