Treated-Color Pink-to-Red Diamonds from Lucent Diamonds Inc.

istorically, diamonds in the pink-to-red color range have been among the most highly prized. In nature, most pink-to-red, brown, and purple colors (and combinations thereof) in diamond have been attributed to the development of defect centers caused by shear stress and plastic deformation. These defects, which gemologists describe as colored "graining," were formed after the growth of the gem was complete and either prior to or during the diamond's ascent to the earth's surface (see, e.g., Orlov, 1977; Many of the world's most famous diamonds owe their color to this mechanism, including such notable stones as the 0.95 ct Hancock Red, the 5.11 ct Moussaieff Red, the 59.60 ct Steinmetz Pink, and the 128.48 ct Star of the South.