Garnet, often thought of by laypeople as a single mineral of a deep red color, occurs in many colors and has a number of varietal names depending on color and composition. Examples include almandite, pyrope, rhodolite, grossular, uvarovite, spessartine, andradite, and demantoid. The latter is the most expensive kind of garnet, usually more expensive than emerald.

Class: semiprecious
Origin of Name: probably from Latin granatum (pomegranate), presumably for similarity in color between the gem and the fruit
Color: red, orange, yellow, green, clear
Chemical Composition: magnesium, iron, or calcium aluminum silicates
Crystal System: cubic
Hardness: 6.5-7.5
Specific Gravity: 3.58-4.32
Geographic Origins: numerous sources worldwide


Photo: ©International Colored Gemstone Association/Bart Curren

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