A singularly unique Kiita straight razor or kamisori sized stone. This kiita tests (Mohs 3), which would likely show-up as a (4-) on the on the western websites scale of 1 to 10. A slurry can be easily raised by a slightly harder slurry stone or like what I use is a well worn older diamond plate such as an Atoma brand.
With super pure and bright yellow minerals, it is the exact opposite of a gray stone. Beautifully formed with a touch of kawa volcanic skin mineral exposed, The stone is solid, and has no inclusions,
 
I have tested this stone on a variety of razors and each type of steel was equally and quickly honed.
 
Size is: 192-70-25mm in thickness. 1.85 lbs.