Cleaning hot stamp chips should only be done by someone with lots of experience. I sometimes clean hot stamped chips and this is what I do:

1) Determine if the chip should be cleaned or not. I will only clean chips that I expect to be able to remove dirt and leave the chip BETTER looking than it did. I only clean chips that are in good condition. A worn chip that is clean just doesn't look right. If the chip has dirt that doesn't look like it will come off easily, I won't clean it. If the hot stamp is flaking, I won't clean it. If I am UNSURE, I won't clean the chip. I will only clean a chip if I relatively certain that I will get a better looking chip when I am done.

2) I clean chips with a worn soft bristled toothbrush and Sterling's Magic cleaner. Even still, YOU CANNOT CLEAN THE HOT STAMPED INLAY WITH A TOOTHBRUSH, it will certainly remove some or all of the hot stamp.

3) Holding your thumb completely over the hot stamped inlay, you can clean the mold and rim with the toothbrush and cleaner, turning it about as you clean.

4) To clean the inlay, but some cleaner on your index finger and gently rub it on the inlay using just the pad of your finger.

5) Don't forget to clean the edges with the toothbrush and cleaner.

6) Gently blot off any remaining cleaner with a soft cloth, paper towel or tissue, DO NOT RUB.

7) Practice first with some current hot stamped chips that are still in use at a local casino. After you done, you can still turn in the rejects to the casino for face value.