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SANIDINE (Potasium Aluminum Silicate) |
 | | Sanidine is a polymorph of other minerals that share the same chemistry but have different crystal structures. |
| | Sanidine does not show the lamellar twinning that is common in microcline and is occassionally present as striations on cleavage surfaces. |
| | Sanidine (and anorthoclase) are a common constiuent in extrusive igneous rocks such as rhyolites, where the rock cooled quickly. |
| mineral.galleries.com /minerals/silicate/sanidine/sanidine.htm (595 words) |
