Nachikuro stone water basin. The marks from the kenzan inside the basin could not be removed.

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This is a listing for a Nachiguro stone water basin. Please refer to the images for size and weight.
I believe this Nachiguro stone water basin is a rare item. The back is inscribed with Nachiguro Suiban (Nachiguro Stone Water Basin).
There are marks inside the basin, possibly from a kenzan (flower arranging frog). I thought it might come off with a pressure washer, but it did not. Please understand.
It would be nice to decorate it with suiseki (viewing stones) by adding Kurama sand, etc., but since the depth is about 7 cm, you will need a considerable amount of sand or gravel. We appreciate your understanding of these points.