Quote Originally Posted by Jimbo View Post
Yes - some you get lucky with and can lap the bottom. But a lot you can't because of the "skin". You really don't have a choice - no point forking out hundreds for a stone you never use because you are not prepared to lap it! An expert on Japanese natural stones can tell more from the surface, colour, and skin than the kanji stamps - I've been lead to believe that some unscrupulous miners will forge the kanji of better-pedigree stones to increase their value. Others might paint the skin so it resembles the skin of a better stone. So the kanji, while very cool, are not the defining feature of a natural Japanese stone. Those who know can tell a quality stone without the kanji. I imagine for these people it's as obvious as identifying a Dalmatian is to a dog breeder - you can put a sign around its neck saying "Poodle" all you want, but they know...

James.
Thats correct, the Kanji really only tells you which mine it came from. The only way to tell if its quality or not is to actually use it. Same with testing grit and hardness.
As I mentioned in my information thread I have found stones, that either don't have the "Maruka" stamp (which increases the value a lot) or the "Nihon Kamisori" stamp, yet they perform equally to the ones that do have the extra stamps