Can't be certain, haven't seen it in exactly this shape and colour, but the curl on the one side is very reminiscent of my Bayel piece, France. They did several coloured glass pieces in the 50s - 70s with these thick vaguely boat shapes, some roundish, some with more angular shapes. Don't know if they have done Alexandrite, though, or whether they were copying other shapes themselves. I've attached a picture of mine for comparison.