I recently sold this platter on eBay, and apart from the fact that it was handmade studio ware from Norway, didnt know much about it. It was quite a large piece at about 28cm in diameter. The kind person who purchased it let me know that Bjorre was the name of a pottery workshop in Oslo that started up just after the war (1945).
They produced mainly decorative items for private homes. They are no longer in production (not sure of the date they closed though). I like the use of green and black, and the design in the middle of this piece.
Tomorrow - make sure you check in to see my find of the week! A piece I've been wanting to get for ages.