Coins returned cleaned

[ngcmember2018]

So, I recently received two coins back that had been cleaned and given XF, and VF details.  Is there any thing that can be done to determine that a coin has been cleaned so I will know not to send it in for grading, or even buy those type of coins?

I use a 20x when inspecting a coin.  Thanks!

[DWLange]

My first thought is that 20x is too strong for grading purposes and for deciding whether you like a coin. Try naked eye first, followed by examination under a 5-6x triplet loupe for grading.

As for learning how to tell a cleaned coin from one with original surfaces, that's mostly a matter of experience. It's helpful to examine a lot of certified coins first, and the best place to do that is a coin show. In addition, the ANA provides brief grading seminars at some major coin shows and a four-day seminar at its headquarters in Colorado Springs. Though you'll have to pay for these classes, they will likely pay for themselves in sparing you from buying coins that won't get numeric grades.

[ngcmember2018]

Thanks.  I ordered a 6x loupe.  For now, I'm using a magnifying glass to pick out the best dimes in a sea of 200 roosevelts that were left in the bank deposit box since 1964.  One by one out of the bank bag.....

[Insider]

The color of the coin is often a good indication of its originality.  Follow the advice above to learn what the color of an untoned coin in your series should look like.  

[ngcmember2018]

Does NGC assign numerical grades and even MS grades for dimes that have a pre-burnished planchet?  I’ve seen these pre-burnished planchets on some cents, too.