
Oh yes, Mark knows of mine. And Andy MacConnell's. And Elizabeth Harris'.
Some (considerable, I think) time ago, Glashaus had one. It is (or was) in his list of sold items. My brother saw one for sale in the 20th Century Modern Fair, last November.
I think I know of the one that sold for over £1,000 in the States, Mark told me of that one. Now there's yours, and one other, I seem to be able to work out from the talk here. I think that makes 8.
However, I don't know if some of these might be the same one circulating, and I've not a clue how many (or few) might be lurking in private collections, never to see the light of the market.
I also have never seen one quite like Mark's, apart from his, with the blue inside, and the "stripey" crizzle, though his is shaped more like yours. Mine's much more like Andy (MacC)'s, without the irridesence, with the colours spreading much more widely than yours.
Mine weighs 1600g (according to my not-very-accurate kitchen scales).