and surface steps, on blue calcite. John A. Jaszczak collection #1491c and photo. |
Etched from gray-white calcite. Note that the step edges are rotated 30 degress from the prism/pinacoid face edges. Click here to compare with other graphite spirals. John A. Jaszczak collection #1744a and photo. |
etched from gray-white calcite. John A. Jaszczak collection #1743a and photo. |
References:
GERDES, M. L. and VALLEY, J. W. (1994) Fluid flow and mass transport at the Valentine wollastonite deposit, Adirondack Mountains, New York State. Journal of Metamorphic Geology, 12, 589-608.
CHAMBERLAIN, S. C., KING, V. T., COOKE, D., ROBINSON, G. W. and HOLT, W. (1999) Minerals of the Gouverneur Talc Company #4 Quarry (Valentine deposit), Town of Diana, Lewis County, New York. Rocks and Minerals 74, 236-249.