Thanks to Ron Hayashi for his reply regarding shelf life of immersion
gold PCBs.

The boards I have experienced problems with are coming up to 18 months
old (I tend to agree with Ron that 6 months is about the maximum shelf
life) but I have also looked at the thickness and quality of plating.
The gold on the board is 0,014 microns thick using XRF equipment (is
this OK?) I thought that seemed quite thin!?

I have witnessed 'pitting' in the nickel layer which, in some cases,
goes right down to the copper.

Can anyone tell me how much nickel / gold should be on the board and
what effect the above would have on solderability / shelf life

Thanks,

Neil Atkinson