Well that makes a BIG difference ! WOW thats heavy !!!
Certainly Scandi quality and the pontil would tend to suggest that too.
I have a Holmegaard one - generally regarded as good to high quality -rather less bonkers than yours. It also has a polished pontil - but only 11" and 2.75 pounds weight with a base thats almost an inch (higher inside than on the surface).http://img.photobucket.com/albums/v489/avalonsmile/Researching/P6297641.jpg
Yours could also be Holegaard, Boda / Kosta Boda or any one of a dozen other Swedish companies.
There's nothing in my Scandi book remotely like it but that means nothing - you'd need a hundred books like it to cover a small proportion of total Scandi output during the 70s which is when Im guessing this dates from.