A Geoscience Digital Image Library
A Geoscience Digital Image Library
| Title | Dolomite and calcite from Black Rock, Arkansas |
|---|---|
| Description | The white “flowers” are calcite, CaCO3 and the salmon colored crystals are dolomite, CaMg(CO3)2. Both are carbonate minerals and it is not uncommon to find them together. This specimen comes from Black Rock, Arkansas, a place that has produced many museum quality pieces. Because of its color and curved crystal habit, the dolomite in this specimen is readily identifiable. Often, however, distinguishing dolomite from calcite is difficult. Calcite is more common and effervesces easily when a drop of dilute hydrochloric acid is applied to it. Many geologists carry acid with them in the field so they can make the “acid test”. |
| Location | USA ▹ Arkansas. Near Black Rock. |
| Photographer | Darla Sondrol. 2001-07-03. |
| Collection | University of North Dakota Mineralogy Collection. |
| Key words | calcite, dolomite |
| Tech details | 581 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60 mm AF Nikon micro lens. |
| GeoDIL number | 1028 |
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