| Term: | small concretion |
| Definition: |
A hard, compact mass or aggregate of mineral matter, normally subsperical but commonly oblate, disc-shaped or irregular. Formed by precipitation of mineral from solution in the pores of a granular rock, localized around a nucleus or center, to define a discrete, sharply separated object. Size ranges from cm to decimeter for application as a compoundMaterialConstituentPart; larger concretions should be considered GeologicUnit parts. |