The Tavern

Currently, tiles uses the question mark to mean either "confused," "hasn't noticed player yet," or (possibly partially) "petrified." I can see the first two using the same icon (though a different icon would be nice), but a question mark doesn't make any sense at all to me for the third. Would the developers be open to using a different icon? If so, does anyone have a good idea of what it should be?

A little grey/gray statue? Shaped sort of like an Oscar idol/trophy?

A representation of the treasury at Petra, Jordan?


Or maybe a grey octagon, like a stone stop sign?