Natural Japanese water stones

Natural stones are graded from their density rather than their grit, making them inconsistent compared to their synthetic counterparts.

Natural water stones require natural nagura stones to raise a slurry in order to manipulate grittiness. This is also a characteristic that differentiates naturals from synthetics which require synthetic nagura stones for cleaning, not slurry formation.

Natural stones are mined and require a very experienced eye in order to grade them. That being said, natural stones bring a whole new level of sharpness and retention to your knives.