I personally like my chips to be clean. I use Armor All Multi Purpose Cleaner and a very soft baby's toothbrush. But if you clean a Hot Stamped chip cover the hot stamp with your finger so you don't ruin it. Then I just wipe the chip dry. If you have a chip thats faded after you clean it put a light coating of baby oil on it and let it dry for 24 hours and wipe off the excess. It works great for me.

Thanks,
Victor