GRD00GFS0
I-676
Rhyolite
Precambrian › Proterozoic › Neoproterozoic › Ediacaran
542.0
-
630.0
1
Ritter 154 › Cabinet 15 › Drawer G
Porphyritic
altered black porphyritic rhyolite. Part of Marblehead Neck volcanic plug (dark fine grained rhyolite and lighter volcanic breccias)
-
-
Massachusetts
Marblehead
Latitude: 42.5°
Longitude: -70.9°
-
Spherulites
5.0
plane
Spherulites
5.0
crossed
-
scan
crossed
GRD00GFT0: Altered plagioclase, spherulites, opaques inclusions in plagioclase (C. Eichler)
N/A
N/A