| Title | Cherty ironstone, similar to taconite |
| Description | This sample contains lighter colored chert with a mix of darker iron oxide and iron hydroxide minerals. It is from the Ironwood formation, Upper Peninsula, Michigan. |
| Location | USA ▹ Michigan. Near Ironwood. |
| Photographer | Darla Sondrol. 2001-07-23. |
| Collection | University of North Dakota Mineralogy Collection #3502. |
| Key words | chert, ironstone, Michigan |
| Tech details | 795 KB. Hand specimen. Fujifilm FinePix S1Pro digital camera; 60mm AF Nikon micro lens. |
| GeoDIL number | 1295 |
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