Mining Rock Boring Bit.
Made from iron and tungsten. Size 3″ x 1 3/4″ inches.
This bit is made from iron and tungsten with an internal copper sleeve and holes for water infusion. This is the common type used in all mines it slotted onto the end of the 6′ foot long boring rod.
The image (left) is to show the difference in their sizes in comparison to each other.