The cool thing I found with the Washita and hard black, is how they perform with different lubes.( water, oil, glycerin, lather, ect.). My Washita can act like three stones, just as the black.

I burnished one side of my black, and left the metal swarf on the stone, to lessen its effects and make it a better finisher. Some time on a pasted strop yielded a nice shaving edge.

For the most part, I use them in a natural progression, instead.

Give it a good cleaning with some spray degreaser, lapp it, and give it a go. You might be surprised..!!