| Harding Sandstone | |
| Type: | Formation |
| Age: | Ordovician |
| Period: | Ordovician |
| Prilithology: | Sandstone |
| Otherlithology: | Siltstone, shale |
| Namedfor: | Harding’s quarry, Fremont County |
| Namedby: | Charles D. Walcott (1892) |
| Region: | Central Colorado |
| Underlies: | Fremont Formation |
| Thickness: | 26to |
The Harding Sandstone is a geologic formation in Colorado. It preserves fossils dating back to the Ordovician period.