 |
near Wenatchee Lake, Washington  |
LOCALITY IMAGES
|
 |
GEOLOGY
Rocks of Wenatchee Ridge consist of ultramafic lenses within granitic gneiss that have experienced high grade metasomatic metamorphism. As a result of metasomatic infiltration of silica into the ultramafic lenses from the surrounding gneiss, the ultramafic lenses are zoned from rim to core, with decreasing silica content towards the core. This chemical gradation is reflected in mineralogical zoning within the lenses: (RIM) phlogopite + actinolite >>> actinolite >>> actinolite + talc >>> talc (CORE).
Collecting is within the Wenatchee National Forest.
MINERALS
|
| Ca2(Mg,Fe)5Si8O22(OH)2 - translucent elongated prismatic crystals found as monomineralic aggreagates, or associated with phlogopite or talc. Crystals are dark green and do not possess terminations. Actinolite in cores of ultramafic lenses are more translucent and brighter in color. |
| CaCO3 - Opaque white to grey cleavable masses from decimeter scale monomineralic calcite lenses | |
| Chromium (Cr) rich muscovite, KAl2(AlSi3O10)(OH)2 - Bright green schistose segregations assocaited with phlogopite | |
| KMg3(AlSi3O10)(OH)2 - Brown to black schistose masses. | |
| FeS2 - Cubes to 1" embedded in silicic matrix. | |
| SiO2 - Milky crystals up to 1" in small cavities. | |
| Mg3Si4O10(OH)2 - Pearly light green to white masses occur with actinolite. |
* photographed
FUSCHITE
|
Massive cleaved |
ACTINOLITE
|
PYRITE
|
ACTINOLITE
|
