Churt Nodule or Possible Marine Fossil
Unknown excavation source
Unknown measurements

A chert nodule in sedimentary rock is a distinct, often rounded or irregularly shaped mass of chert, a hard, fine-grained, siliceous sedimentary rock, formed within a host sedimentary rock such as limestone, chalk, or shale. Found embedded within sedimentary rocks, most commonly limestone or chalk, but also in shale or dolomite. They often stand out due to their hardness and resistance to weathering compared to the host rock.

This example does have a distinct "claw"-like form. Yet, from images alone- I do believe it to be geologic and not biologic in formation. I am one opinion, if you would like to research your example further; I do suggest an in-person assessment. You can schedule an assessment with a regional University or Field Museum Geology department. You could also contact your local library to discover more resources for research on churt nodule formations or when geology and rock and mineral shows are in your area. There are also paid services with regional auction houses and appraisers.