I have noticed that on some proof coins like the 1981-S Washington Quarter that I have it is goldish in color. Now is this just an effect of toning that is occuring or whats goin on, I know it not actual gold but it looks that way.
ok here is one one ebay that i found, it would almost seem like its being caused by the light but the one i have is the same. http://cgi.ebay.com/1981-S-GEM-PROO...Shipping-/120578326104?pt=Coins_US_Individual
The golden hue you see on your 81-S quarter is quite natural for that era. Many clad proofs from 79/80/81 (half, quarter, dime) have naturally toned to this golden color. Some find it appealing, others look for un-toned specimens, it's just a matter of taste. Happy Collecting