Longines quartz history assistance required

[HarryW]

My son inherited a nice Longines, I think circa late 70's or early 80's. It's square faced (rounded off corners), 9kt gold, gold face, black roman numerals & hands, date window and a blue jewel on the end of the winder.
From what I can make out its a L731.2 with a ESA(ETA) 940 111 7 jewel quartz movement.

I've tried google but can't find any reference to this kind of watch and am interested to understand what age it is etc. Is its lack of google search result an indication its rare or just rubbish !

I realise most think quartz is the devil (so do I to a degree) but early quartz is Longines so not so bad imho.

Links to Longines sites that have reference appreciated if you don't have a direct answer.

[HarryW]

I can but assume because I put 'quartz' in the title this thread is going to be ignored

[glazbagun]

I'd reccomend posting in watchuseek- they have a High-End Quartz forum which has some very knowledgable quartz nuts. Your sons doesnt sound like a V.H.P, but there's more chance of someone there having a clue than here.