My friend got this Japanese waterstone as a gift, and she's teaching herself how to sharpen her knives. I mentioned to her that soaking time is highly variable: some stones are splash-and-go, some are 15 minute soakers, and some are happiest living in a bucket of water. She doesn't know the brand of the waterstone, and she can't read the kanji to to figure out how long to soak it. She doesn't want to wear it down prematurely, so she's hoping to find out what kind of stone it is, and how long to soak it. Anybody recognize it, or can anyone read the instructions on the box? Here are some pics of the box it came in? Thanks!