While I was looking through some of the Russian coins and images that I had, there were some that I definately wasn't paying attention until I looked VERY hard. One of which was the example of the counterfeited 1830 ruble that I was fooled into.

Such is the example of this:



1759 2k over 1755 1k over 1727 5 kopeks, which was discussed here: Link

Because of the extreme nature and bruteness of overstriking, years usually get wiped and it is already quite difficult to get three years on a single coin, although what is more amazing is if you can even find a mintmark under cruelty. And just a few days ago, I think I just found it - just located 15 degrees off the St. George's helmet, leftwards, there seems to be the mintmark:



This is quite undeniably the mintmark of MMD, or the Moscow Mint. I cannot help to say that I am quite overwhelmed over what I have, and I still thank Banivechi for this

Another coin that I wasn't paying attention to was a coin that I bought while I was still in Moscow and thought it was too expensive. I think I picked it up for 6-10 dollars but with this novelty and it's aUNC condition, I am quite happy to say that I DID bought it.



At first glance, you would not really notice much, but here is a larger image:

Notice at the denomination 50 and the hammer and sickle area at the obverse. This is indeed quite clear that a die clash has occured, like what Tane has!

Ironically, I didn't notice this error until quite recently... which is over 3 years since I bought it...

Morale of the story - do check what you have bought!

Wait, typically, are not errors supposed to bring up the value of the coin? (Naive me - ready to learn.)

Yes, all mint errors do bring up values, although I am not too sure if there is really any mint errors that actually decrease their values.

1755-ММД 1k. This makes sense because the 1755-57 "Eagle in Clouds" design undertype was itself an overstrike and I think that it was the overstruck examples of this type that carried a mintmark, while those struck on new blanks did not (I seem to remember reading that somewhere).

Good observation. You are lucky to have such an unusual coin with the 3 legible dates and a mintmark as well.

If you include things like clipped planchets, striking through grease-filled areas, etc. then the value might even decrease depending on the severity of the error.

Die breaks are usually innocuous and merely curiosities. Die clashes, while never decreasing a coin's value, also seldom increase its value but are nevertheless interesting. Error collectors might pay a little more for a nice coin with a die clash.

Sometimes, die clashes are important in determining things like a Morgan dollar VAM variety. But most of the VAMs don't contribute much, if aything, to a coin's value, only the sought-after ones.