Need some help please. Got a dubl duck Russian no. 53 strop on Ebay. The leather is very different than any other strop I own.

The leather has a heavy draw and the leather seems to have cracks but the draw is smooth. Especially after I sanded it down. But it seems no matter how much I sand it down the cracks are there. Even though it is smooth to the touch

I know there is a duble duck Rhino strop. Could this also be rhino? The back of the leather strop has a diamond pattern
on it

Any help is very much appreciated