Antique Mortar & Pestle? Native American Fire Starter Rock Stone Fetish Sioux?

Description

This is a very old, antique Mortar & Pestle? Native American Fire Starter Rock or Stone. Found in corn field while picking rocks in 1980’s area Sioux tribe originally in this area. Brought home set in garage, kid painted it green?? Paint is now peeling selling as is. Items were not found exactly together but in same field. Looks like same type of stone. (Hey any additional information you would be willing to share it would be greatly appreciated)
Items are preowned & sold as shown. Please view carefully. Shipping and packaging $8.00 within the continental USA only. No international sales. Thanks