This piece with anthropomorphic visual qualities was found in the context of a life size stone face mask to be seen soon on this blog. Whether this object is a curated naturefact, or an artifact (human modified), is not as important as the context and similarities to other suspected culturally mediated forms from amateur identified prehistoric cultural sites around the world. This author thinks some artifactuality is present here, but difficult to detect because of its subtlety, the rock material, and its age since human deposition.
Alan as seen in these two stone faces with zooanthropomorphic forms incorporated into the chin and many other figure stones from his site #33GU218 (Ohio archaeological inventory).
Here is a link to another recent posting from Tira's Thailand finds.