A Geoscience Digital Image Library
A Geoscience Digital Image Library
| Title | Twinned calcite from Cumberland, England |
|---|---|
| Description | This is an example of calcite forming a “butterfly twin.” The right and left halves of the sample have different atomic orientations but share a common plane of atoms. Note the “reentrant angle” on the lower front surface. The specimen is about 7 cm across and, unfortunately, has been scratched by students conducting hardness tests. |
| Location | England. Near Cumberland. |
| Photographer | Twyla Baker. 2001-06-11. |
| Collection | University of North Dakota Mineralogy Collection #628. |
| Key words | calcite, twin, England |
| Tech details | 400 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens. |
| GeoDIL number | 687 |
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