The Kuro Nagura is a Japanese auxiliary stone used to create a sharpening slurry on finishing stones. This slurry improves polishing, reduces friction, and allows for a finer and more consistent edge.

Particularly suitable for natural stones and high-grit synthetic stones, it produces a dense slurry that promotes a high-quality finish. Compact and durable, it is protected by a side coating that limits the risk of cracks, making it an essential accessory for precision sharpening enthusiasts.