Valuable Natural Whetstone Finishing Stone Similar to Shiro Nagura Whetstone Large 218×70×60 2.35kg

This is a natural polishing whetstone with distinctive beige and brown stripes. It is a finishing stone with a very hard and smooth polishing surface.
(Photo ③)
Approximate dimensions: 218 × 70 × 60 (mm)
Weight: 2.35kg

◆ This whetstone was passed down to me as Shiro-Nagura whetstone by my late father, who was knowledgeable about whetstones. Our family business was founded in 1910 as Yamaki Ryokado Kanamono-ten and was renamed Morozumi Tetsukido by me, the fourth generation, and has been in business for 26 years.

◆ Before listing, I tested this whetstone against whetstones with grit sizes of #4000 to #6000, using the split surface, not the polished surface. The result was that this whetstone is indeed harder, and its grit size is estimated to be #6000 or higher.
Based on the above, this whetstone is listed as a whetstone similar to Shiro-Nagura whetstone.

※ Thank you for the various comments received after listing.
※ Due to valuable comments such as It's a volcanic rock (altered rhyolite) Amakusa whetstone because it has holes where volcanic gases passed through, I have not definitively identified it as a Shiro-Nagura whetstone.
◆ Incidentally, after researching, it appears that some Shiro-Nagura whetstones do have numerous small holes.

※ If you wish to purchase a genuine Shiro-Nagura whetstone with absolute certainty, we recommend purchasing from whetstone specialty stores or from businesses that mine and produce whetstones in the Shiro-Nagura whetstone producing regions.

◆ Initially, I listed this item as No noticeable scratches or dirt. However, as I plan to use it again for verification of whether it is indeed a Shiro-Nagura whetstone, I have changed the condition to Slightly scratched or dirty.
◆ I may add photos or comments in the future regarding the verification process, the hardness of this whetstone, and my experience sharpening blades.

◆ Please note that if this item is purchased by a customer in my store, the listing will be withdrawn. Thank you for your understanding.

◆ This is a very precious whetstone to me, so I have adjusted the price to my desired amount for this listing.

◆ The item will be carefully packed with cushioning material before shipping.

◆ It will be shipped via Yu-Pack, YuYu Mercari便, or RakuRaku Mercari便.