Basaltic Tuff Breccia of Actinolite Greenschist

Title

Basaltic Tuff Breccia of Actinolite Greenschist

Alternative Title

Chlorite - Muscoivite - Greenschist

Identifier

TMJ-14

Description

Rock Sample:
The sample is brown to white to green in color. It is porphyritic and has foliations that fan out. There are also wide fractures (≤1mm in length). There is a brownish orange coating which is evidence of chemical weathering. There are some holes around the oxidation zones which suggest deep weathering by a liquid. The sample does not react with acid. It has a silty yet jagged texture.

Thin Section:
There are micro-fractures that are non-uniform. The sample is holocrystalline. The majority of the matrix intergrows within many of the larger crystals. The rest of the thin section has a matrix that cannot be identified from a standard microscope.
-Chlorite (30%)
-Muscovite (10%)
-Serpentine (5%)
-Epidote (5%)
-Magnification at 4x/0.10

Date

1969

Contributor

Western Minerals, Inc.

Spatial Coverage

Tanzawa Mountains, Japan Southern edge of (Zone IV)

Temporal Coverage

N/A

Accrual Method

Purchased from Western Minerals Inc.

Unit

Greenschist Facies (Zone IV)

Number of Thin Sections

1