Gold in spectacles

Hello all, in sorting through some bits and pieces, I have found that my mother has kept my grandfather's old spectacles. Initially I thought this was just for sentimental reasons and didn't think anymore about it but on closer inspection, I can see that the arms of one pair has GOLD written on them followed by some numbers (although nothing recognisable like 9ct etc). Does anybody know if it is worth me keeping these glasses, worth getting this gold valued or might it just be plated? My grandfather died in 1973 so the glasses are from around that late 60s into the 70s. Many thanks.