Hello!
I have bought and refurbished a couple of Mazzer Super Jolly grinder in resent years. The newer models with the serial number are easy to date, but older models do not have a serial number.
Are there any other way to tell how old a Super Jolly are?

Different logos at the back of the grinder?
Integreted coffee tray?
Looks of the doser?

The internet lacks a good "The history of Mazzer" site

//Simon