I declined the offer saying that I was shy of the money. "You can pay any time." He was insistent. I settled him by telling him of my having no intention of purchasing it even if I had the necessary money. Again next time, he yanked in a big writing stone slab about the size of a ridge-tile. "This is a tankei," he said. As he "tankeied" two or three times, I asked for fun what was a tankei.