Maruo Ao Suita, nagura size

Size (mm) / Weight

87x47x36 / 335g

Performance

Hardness / Fineness: 3+ / 3+

While the very skilled and determined could possibly use this stone for in hand honing, it would be best used as a tomo nagura for stone conditioning or honing. 

Aesthetics & Other Notes

Simple grey-blue base coloring with some lines and namazu.

This stone is not sealed but remains fully stamped. 

Maruo (丸尾山, Maruoyama)

One of the few that continues to be operational, this Western mine is renowned for its soft shiro suita. This mine is also well regarded for its shiki uchigumori (tenjyou suita), ao suita, and aisa-layer stones. Once widely available and relatively cheap, increased demand has outpaced supply making these stones harder to get and more expensive than just a few years ago. All things considered, however, they are comparatively still quite attainable.