hen was the launch date of the Tropic-Proof design by Alpina? That was the first question on the table. The exact date is hard to pin down; concepts such as collections, ranges, product lines and inventory were much more loosely defined in those days.

History records an official launch in 1968, but there is evidence of the ‘Tropic-Proof’ name being used right from the early 1960s; careful analysis of serial numbers 760XXX-809XXX suggests that production first started in 1965.   ‘Tropic-Proof’ referred to a certain type of watch construction and was characterised first and foremost by a case marked with the initials ‘FB’ for François Borgel. In the early twentieth century, Borgel was a leading Geneva casemaker.

Like many other brands, Alpina commissioned the firm to make their toughest cases and more especially those with screw-down casebacks. The Tropic-Proof designation also called for the use of some of the finest Swiss calibres, such as Alpina’s hand-wound 598R movement.