Tag Archives: garnets

Madagascar: A Gemologist’s Journey (Sahatany Valley Pegmatite Field)

Posted on October 10, 2014 by mrahm

Our day in the Sahatany Valley was a long one, so I’ll split it up into two consecutive posts. Sahatany Valley is of the most famous and productive pegmatite areas in Madagascar. This gorgeous valley is known for producing polychrome … Continue reading →

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Garnet Chemistry

Posted on January 14, 2011 by mrahm

While all garnet species share the same crystal structure, they differ chemically. Garnets are divided into two groups: those that contain aluminum, and those that contain calcium as part of their basic chemistry. Aluminum garnets are generally reddish due to … Continue reading →

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Garnet Species & Color

Posted on January 13, 2011 by mrahm

In one of my previous posts, I discussed the various colors of garnet. In many cases, the color is a good indicator of the garnet species to which it belongs. There are five commercially significant garnet species out of the … Continue reading →

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