What am I?

[debunix]

My friend in Japan sent me a gift box with various neat things (chocolate, a book) and one item that came in a little transparent plastic ball, made invisible (and protected) by a bubble-foam layer. It was apparently from one of those machines where you feed it with a coin and then pick a ball and hope it has a cool prize inside.

And....this little thing was inside:



It has quite a lovely glaze/ash/finish, iridescent and sparkling, really neat.

But....what might it have been intended for?

I haven't been able to figure that out. It's the wrong shape for a chopstick rest, and a bit small for a spoon rest; but of course it works beautifully as a presentation tray for a nibble of fine chocolate with a tea session.

[Bok]

Don’t think Japanese need a reason to make a special plate for a special tiny thing )) could also be for soy sauce for sashimi.

[debunix]

It would be just deep enough for a little splash of sauce, but would hold something like wasabi more effectively because it is so shallow.