Nikkor 50mm f/1.4 completely in gold

[akopf]

We have found an interesting lens as part of an inheritance, but we can't really categorize it. It is a 50mm, 1.4mm (see photos) that is all gold - not like the Nikon FA Grand Prix where the lens only has a gold adjustment ring.

Can anyone tell us more about the history of this lens - how many are there, when was it sold and why?

Best regards,
Andreas