"Blue Eyes Granite" - coarsely-crystalline anorthosite from the Precambrian of Canada.
Anorthosites are uncommon intrusive igneous rocks almost exclusively composed of Ca-rich plagioclase feldspar. There’s usually a blackish pyroxene component as well. Anorthosites having labradorite plagioclase feldspar will display a wonderfully colorful iridescent play of colors (labradorescence). This makes them desirable decorative stones.
All of the lightish to darkish gray material in the polished decorative stone surface shown above is labradorite - every crystal will flash bright blue when tilted at the correct angle in the light. This expensive decorative stone comes from the Ten Mile Bay Quarry, near the town of Nain along the Labrador coast, eastern Canada. The quarry exploits the Nain Anorthosite (Nain Plutonic Suite), a mid-Mesoproterozoic intrusion (1.29 to 1.35 billion years) emplaced along the Abloviak Shear Zone.
Loading contexts...
