Silver plate will eventually tarnish just like sterling silver and fine silver. Polish it to brighten it back to its original shine, but be gentle. Vigorous polishing can remove the silver plating and expose the base metal below.
Leather can contain hydrogen sulfide, which tarnishes silver and can lead to deterioration of silver plating. We recommend not using silver plated jewelry chain with leather cord.
Rubber bands also contain sulfur, which tarnishes silver. Do not place rubber bands on silver plated jewelry (or even on a plastic bag containing silver plated or sterling silver jewelry).
White plated chain does not match the color of sterling silver as well as silver plated chain, but because the surface is "silvertone" (usually rhodium), white plated chain keeps its shine longer.