A mineral of high-grade and high-pressure metamorphic rocks. Usually fairly good crystal form. Moderately high relief. Pleochroic in shades of yellow, and often riddled with inclusions. This texture is called poikiloblastic.
Has low birefringence and looks pretty much the same in both plane and crossed polarized light.
A very typical example of staurolite in plane-polarized light, showing high relief, yellow color and poikiloblastic texture.
Same field under crossed polarizers. The dark color is due to being near extinction.
Same field rotated to maximum color.
Another typical example of staurolite in plane-polarized light.
Same field under crossed polarizers. Note that there is almost no change in color.
Created 10 Oct 1997, Last Update 14 Dec 2009
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