In some minerals color is directly related to a metallic element, is characteristic, and can be useful in identification. As examples,  azurite as shown in Figure 1A, is always blue. . . Read More

Lattice Defects, Impurities and Color As stated in references 17, 18 of my DIAMONDS II blog, impurity atoms and lattice vacancy defects are responsible for the coloration of diamonds [Ref. . . Read More

A Gallery of Natural Diamond Crystals The gallery includes clear crystals and those exhibiting a range of colors (Figures 2-13), a range of shapes (Figures 2-15), examples of inclusions found. . . Read More

In this blog, my second on diamonds, I’ll discuss the physical and chemical properties of a diamond, then its optical properties in relation to its crystal structure and chemistry, and. . . Read More

Having greatly enjoyed writing my last blogs on garnets as gemstones and mineral specimens, topics different from my long-time interests in the ore-forming minerals, I am starting a series of. . . Read More