Naming Andesine-Labradorite

Modified: April 2011

The name "andesine" comes from the Andes Mountains, where it was first found, and "labradorite" was derived from Labrador, Canada, where labradorite (the labradorescent kind, not the transparent kind) was first discovered. So why hyphenate it? Chemically speaking, our material falls between andesine and labradorite, so we chose to hyphenate and use both terms to be more accurate and descriptive.

Andesine and labradorite are two distinct minerals with very similar chemistry. How do mineralogists determine which is which? By the percentage of sodium to calcium within their structure. As a matter of fact, when the percentage of sodium and calcium is equal (50/50), they are one and the same. This may not happen often, but it does create a gray area on the dividing line. This close relationship between the two minerals also creates another dilemma: Gemologists cannot separate the two with the standard array of tools available to the trade.

Since their chemical, optical, and physical properties overlap, every stone would have to be sent out to major universities or laboratories for individual identification. This involves substantial time and cost. To avoid that added cost, JTV coined the combination name "andesine-labradorite," because tests show that our material falls within those boundaries. Since their beautiful color was the determining factor in purchasing these red and green varieties of feldspar, not their exact chemical composition, we felt this was the fairest, most accurate name for this material. Authorities in the gemstone industry agreed that this was a responsible way to identify this product.

Andesine-Labradorite Mix