Desertcart Logo

Q: Has anyone had a coin graded using this solution

I have had many SILVER coins successfully graded using the old formulation, which was mostly sodium hydroxide (lye). Sometimes the lye attacks bronze coins- not the copper but if there is some tin in there it will react badly. The last couple batches of MS-70 I bought used an ammonia based cleaner (windex with some dish soap added?). They new formula does not clean nearly as well as the old, but it certainly won't harm the majority of your coins. Just the act of handling them subjects your coins to potential damage but the chemicals shouldn't hurt the base metal, at least not pure copper or silver. You might want to swab a small spot on the edge to confirm the coin is safe before exposing the entire coin to MS-70.

Q: Is this product effective for removing copper tarnish?

I have experience with the older formulation, which you would not want to use on brass or copper, only gold or silver. It's probably actually the tin content in the copper alloy that ends up getting attacked by MS70, so if you have pure copper it might be OK. Try a test patch first. These guys have since changed their formulation from lye to some kind of ammonia based house-hold style cleaner that is probably harmless. If the MS70 is clear and slimy feeling, test a small out of sight area on copper before going at it whole hog and if it smells like Windex, then it is probably ok to use but might not actually do anything but remove dirt and not touch tarnish. Sorry I couldn't do better but copper is kind of a tough call because of all the alloys.

Q: So Ive been using this product for a while and it left a strange film on one penny and another has a rainbow look on it?

I have never tried it on cents so I can't give an honest answer here. It is supposed to brighten the coins not thoroughly clean the coins. Other dips are better for that which I don't like to do. I have used MS-70 on already clean coins and Proof coins that needed enhancing. For that it is outstanding.