I recently got my hands on the Nubatama stones from Ken Schwartz at Precise Sharpening, aiming to expand the Edge Pro custom stone lineup. Although I’m not planning to carry the entire range—28 stones split into the higher Bamboo series and the lower Plum series—these stones offer unique properties beyond just their price points.
The classification by series doesn’t necessarily denote quality; it’s more about finding the right match for specific knives based on steel and style rather than the series alone. With overlapping grits and distinct properties, it can be a bit of a challenge to keep track of their individual characteristics.
While experimenting with these stones, an opportunity arose to work on a special Japanese Damascus yanagi for a sushi shop I service. Without capturing a ‘before’ picture, I began the process, typically being a devoted user of Shapton stones. The initial shaping with belt sanders and subsequent work with the Plum and Bamboo series revealed fascinating characteristics of each stone.
The 180 Plum worked wonders in eliminating belt scratches on clad steel, offering a solid feel akin to Chosera with the aggression of a 180 grit. Progressing to the 320 Plum, it created an even 320 grit scratch pattern with a subtle indication of a beginning polish.
The 400 Bamboo stone surprised me—it doesn’t involve shaping but moves straight to polishing, releasing abrasive to form a paste while retaining its solid structure. Moving through the Bamboo series, each stone seemed to know the right amount of abrasive to release, gradually revealing the Damascus pattern with varying levels of contrast.
The 2K Bamboo stone’s softer, chalky texture and the 4K Bamboo’s surprising interaction with softer damascus steel were intriguing, showcasing different polishing properties.
While I didn’t explore the full range of these stones due to time constraints, these Nubatama stones seem to cater more to polishing and aesthetic sharpening rather than traditional sharpening, offering a potential synthetic alternative to Japanese Natural stones. There’s still much to learn about these stones, but they represent a unique approach, focusing on creating a beautiful finish after the initial sharpening work.
Apologies for the lack of visuals, but hopefully, this overview sheds some light on my initial experiences with the Nubatama stones!
