This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Evens and Howard firebrick. Evens Howard Fire Brick Co Found at the Joliet Iron Works ruins park in en Joliet Illinois Originally marked as Fair use but as the manufacturing stamp is text only it is not eligible for copyright own by uploader originally on English at Image Firebrick Mendaliv Brick stamps Joliet Illinois