|GOETHITE, ROCK ISLAND DAM, DOUGLAS COUNTY, WA|
5-21-86 No. 122 5KV APER200 x500 by CMN
|THIS TABLE LOOKS BEST WHEN VIEWED USING INTERNET EXPLORER.|
MAGNIFICATION FIGURES ARE FOR THE ORIGINAL SEMs, NOT FOR THE IMAGES YOU SEE ON YOUR COMPUTER SCREEN. I WILL BE ADDING SCALE BARS WHEN I HAVE TIME TO DO THE CALCULATIONS.
Dark yellow brown to deep coffee brown on top; sepia-colored in corss section. Interlocking semispheres of fiberous crystals, sometimes growing out of a base of massive, red to yellow brown, translucent resin. Occurs as cavity linings, where it is always the first thing to grow, and, occassionally as spheres growing around erionite or offretite rods. Possibly intergrown with clay minerals.
5-21-86 No. 121 5KV APER200 c. x5000 by CMN
Closeup of the specimen seen in SEM no. 86.