Is this a Jnat?

[Borgroves]

Standing at the brink of the rabbit hole, looking in... Bought at an auction, no stamps that I can see. I haven't laid hands on it yet so I have no idea how it feels, or what it sharpens like. Any insights would be greatly appreciated! Thank you

 

[tostadas]

The stone looks to me kinda like the imanishi/amakusa white natural stones. Maybe someone who can read the label can confirm.

 

[Nino-chan]

Looks quite like a Binsui Jnat (Medium grit stone)