I could hear the difference when I tried silver cables. Clearer and sharper. I disturbed me to know that the type of metal made a difference.
I subsequently upgraded to silver throughout, and I am very happy with my sound.
My interconnects are AudioQuest AudioTruth Diamond X3 and my speaker cable is AudioQuest Dragon.
I noticed the price of silver went up substantially in later years and cable manufacturers seemed to switch away back to copper and silver coatings.