thanx for the report from Japan. Some buddies and I have had long talks about going there from some beach hunting. If we only could time it in such a way as to arrive during erosion cycles (I dislike random dry sand hunting).
Because where I'm at in CA gets a lot of Japanese tourists (Monterey/Carmel golfing and tourism). And invariably, they look at you like you're from outer space. They simply have no concept of the idea of a metal detector. Nor could understand why someone would waste their time. They think we must be city employees or something, and ask "what are you doing?" etc...
This has caused me to figure that the hobby must not be that big in Japan. And if so, then the affluent economy (people wearing "bling"), and the high value coins ($1 and $5 as common as we carry quarters and dimes) should make for good beach action there.