الوصفSodalite-aegirine-albite pegmatite, Ice River Complex BC.jpg
Sodalite-aegirine-albite pegmatite (field of view ~7.1 cm across) from the Ice River Complex of British Columbia, Canada.
Blue = sodalite
Very dark green = aegirine pyroxene
Whitish = albite/sodium plagioclase feldspar
Here’s an unusual rock that represents a cavity-filling in a pegmatitic syenite. The syenite host rock is dominated by large, whitish albite crystals (= sodium plagioclase feldspar, NaAlSi3O8) (see left & right edges of photo). The cavity fill has nice, large, bluish sodalite crystals (= sodium chloro-aluminosilicate, Na8(AlSiO4)6Cl2)). Surrounding each sodalite is a radiating spray of very dark green needles of aegirine pyroxene (= sodium iron silicate, NaFeSi2O6).
The rock comes from southeastern British Columbia’s Ice River Complex. The Ice River is an 18-kilometer long, 29-square kilometer, backward J-shaped alkaline igneous intrusion emplaced in Cambro-Ordovician passive-margin limestones and shales.
Age: ~356 million years (Tournaisian Stage, Early Mississippian)
نسب العمل إلى مُؤَلِّفه – يلزم نسب العمل إلى مُؤَلِّفه بشكل مناسب وتوفير رابط للرخصة وتحديد ما إذا أجريت تغييرات. بالإمكان القيام بذلك بأية طريقة معقولة، ولكن ليس بأية طريقة تشير إلى أن المرخِّص يوافقك على الاستعمال.
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