A Geoscience Digital Image Library
A Geoscience Digital Image Library
| Title | Aragonite “toadstool concretions” from Slope County, North Dakota |
|---|---|
| Description | Aragonite (CaCO3) has many different habits. These mushroom-like aragonite nodules come from a bentonite in the lower Brule Formation (Oligocene). They are about 3 cm across. Aragonite is a polymorph (has the same composition but different atomic arrangement and crystal forms) of calcite, which is more common. |
| Location | USA ▹ North Dakota ▹ Slope County. Near Amidon. Chalky Buttes, SW 1/4 sec 30, T. 134 N, R 100 W. |
| Photographer | Nessa Eull. 2001-06-13. |
| Collection | University of North Dakota Mineralogy Collection #687. |
| Key words | aragonite, North Dakota |
| Tech details | 356 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens. |
| GeoDIL number | 729 |
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