This super dense and hard stone would be considered a final finishing stone for the ultra-keen needs. The stone, as it sits, will only burnish a blade, and it would be useful in trades that require micron-sensitive blade edges. A dot of water from a finger will stand proud for hours before evaporating, while flattening and evaporating before dispersing.
Dense at 359 grams, at 11x7x2mm thick, the gray tomae back, and the straw colored top surface are of the same hardness at 6 on the Mohs scale as measured with a Mohs kit.
Both front and back surfaces are flattened to machinist tolerances.