I didn't know that - good to know.
Btw - as for pieces done at Hadeland, the artist would usually sign his/her own work, while the same designs
blown by anyone else would be signed with the artists "artglass number" and Hadeland.
Some pieces are signed by designer, glassblower and or engraver together, usually only espcially fine pieces.
Pieces designed, but not made by Benny Motzfeldt at Randsfjord will not be signed, if made by her they will be signed B.M YYYY or B.M. YY ( very rarely full name ). At Plus her designs were etch marked Plus BM, if made by her signed B.M etc.