Your link wasn't working (it appears that you pasted the link twice into the link box) so I rearranged it so that it would work.
It appears that your Grandfather's gun has been plated, gold hammer and possibly brushed nickel on the body of the gun.
That really hurts collector's value.
"The gift which I am sending you is called a dog, and is in fact the most precious and valuable possession of mankind" -Theodorus Gaza
Baby Jesus cries when the fat redneck doesn't have military-grade firepower.