Weathered dunite, Newdale, NC

Click on image to enlarge          Photo © Daniel R. Snyder

Above: Weathered dunite, with small grain size and indented grain boundaries resulting from cataclasis and subsequent weathering. All of the blue-green olivine grains clustered at left center go extinct simultaneously, indicatng that they are fragments of a single crystal. Note the dense network of dissolution channels and voids (black). Newdale, Yancey County, North Carolina. XPL digital mosaic. Imaged area 1.3 mm x 3.2 mm.

Below: Optical scan of a freshly-sawn surface of weathered Newdale dunite, same sample as above (NOT same scale). Yellow-orange color is imparted by hematite, disseminated in serpentine layers between and within olivine grains. In the high-magnification view, many of the more robust olivine grains can be seen to retain a light yellowish-green color. Dark grains at lower left are chromite. Dark green grains in cluster at upper left may be remnants of a fragmented hornblende grain. 2400-dpi optical scan. Imaged area 11.4 mm x 17 mm.

Click on image to enlarge.          Photo © Daniel R. Snyder