GRD0011S0

I-39

Rhyolite

Cenozoic › Neogene › Miocene
5.3 - 23.0

1

Ritter 154 › Cabinet 15 › Drawer F

porphyry,resorption,crystal rich

Original label: Rhyolite with minor blue zoisite.

Age data from McCurry et al 1988, found in USGS Preliminary geologic map of the East Mojave National Scenic Area, California

Van Winkel Mtns

California
Van Winkel Mtns, 30 mi NE of Amboy
Latitude: 34.99°
Longitude: -115.29°

-

Large embayed potassium feldspar with euhedral amphibole.

2.5

plane

Large embayed potassium feldspar with euhedral amphibole

2.5

crossed

-

scan

crossed

GRD0011T0: Large plaigoclase (polysynthetic twinning) with twinned crystal growth, smaller plagioclase with albite and polysynthetic twinning, euhedral hornblende, plagioclase glomerocrysts. Resorbed minerals: plagioclase, sanidine, amphibole, quartz, biotite (C. Eichler)

N/A

N/A