| calcium oxide |
| maguey (fiber)/cantala (fiber) |
| carahuasca (Rindenliane) |
| carbonate rock |
| ceder (wood) |
| ceramic and ceramic by product/cerámica y productos cerámicos |
| chalcedony |
| chambira-Faser/fibra de chambira |
| chert |
| claws (animal components) |
| clay by composition or origin |
| clay by function |
| clay by product |
| clay by product |
| coal |
| coating (material) |
| coating by composition or origin |
| coating by form |
| coca |
| collagenous material |
| combination inorganic/organic material |
| components (objects parts) |
| components by specific context |
| copper alloy |