*Basalt

A mafite (dark colored igneous rock) or basaltoid containing mostly calcic plagioclase, clinopyroxene +/- olivine, orthopyroxene, foids, oxides and rarely quartz.
17 Pins
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3 Sections
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1y
By
Kim_in_MN

Vesicular Basalt

1 Pin
Tumbled Writing Rocks

Porphyrytic Basalt

7 Pins
"I love amygdaloidal basalts. I picked these little beauties up in a gravel pit. Lake Superior is famous for these amygdaloidal basalts (a fancy term for a basalt with mineral-filled vugs). Sometimes the \"filler\" is agate, sometimes laumontite in a beautiful orange-pink, sometimes epidote in an olive green, sometimes prehnite. These samples capture the diversity available in my wonderful state of Minnesota! The epidote is particularly vivid on one of these, and the pink fill is so neat on anot

Amygdaloidal Basalt

8 Pins