help me identify this lamp  

I bought this lamp on a vintage market in the north of France. it has no labels, no 'made in...', nothing. i have asked around on countless forums without result. this is the info i do have. it uses a bayonet socket (which was commonly used in the 70's mostly in the UK) and the plug does not have a ground pin (wich means it's not made post 2000). the size is 9cm base diameter and 45cm height. the inside is sand blasted and the entirety has a high quality production so i doubt someone just made it for fun. my theory is that it was a prototype by a company. 

as a design student i would really like to find who made this and what the story behind it is. thanks for the help.