This style of dial, with a combination of Roman and Arabic numerals is colloqially known as the 'California dial'. The term only began to be used widely in the eighties, when a redial company based on California refinished large numbers of Rolex Bubbleback dials in this style. Of course the Roman and Arabic number mix predates that, the original Panerai ref. 3646 dates to the 1930s, and Rolex was using this design some years before that, and the original 3646 was made by Rolex too.
This message has been edited by SJX on 2007-02-28 19:08:55