| Title | Graywacke from Mentone, California, USA |
| Description | Graywackes are “dirty” sandstones. That is, they are sandstones that are poorly sorted and contain significant amounts of rock fragments and clay besides the normal quartz. This sample is 9 cm across. |
| Location | USA ▹ California |
| Photographer | Nessa Eull. 2001-05-21. |
| Collection | Ward’s University Rock Collection #145. |
| Key words | graywacke, California |
| Tech details | 1.02 MB. Hand specimen. Fujifilm FinePix S1Pro digital. |
| GeoDIL number | 477 |
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