Clay and Stilbite Matrix in Sandstone

Title

Clay and Stilbite Matrix in Sandstone

Alternative Title

Quartz Sandstone

Identifier

TMJ-17

Description

Rock Sample:
The sample appears to be a conglomerate of crystals.The color is tan to dark green. The rock has low specific gravity . There are green, white, and brownish-orange clasts. There are some minor fractures on the outside of the sample. There is some very light banding of minerals. There is an orange coating that could be evidence of chemical weathering.
It has rough sandy texture, and is very brittle.

Thin Section:
There is a very fine matrix with semi-rounded quartz and multiple zoned crystals. The crystals are very disorganized within the thin section. Some of the plagioclase crystals show non-uniform twinning. It is similar to tartan twinning, at a 70 degree angle. Some of the pyroxene is very fine grained and are clumped together in a swirling formation.
-Quartz (40%)
-K-feldspar (20%)
-Plagioclase (20%)
-Pyroxene (15%)
-Biotite (5%)
-Magnification at 4x/0.10

Date

1969

Contributor

Western Minerals, Inc.

Spatial Coverage

Tanzawa Mountains, Japan in sandstone of (Zone I) 100-150 feet from locality sampled

Temporal Coverage

N/A

Accrual Method

Purchased from Western Minerals Inc.

Unit

Zone I

Number of Thin Sections

1

Geolocation