Silver-Plated Fake In Slab - Or Not?

It is the same coin ... the NGC images were probably done long ago right after being slabbed, and the HA images are current because the auction is still running.

We know it is the same coin because of the certification number on the slab.

My question was: Is this coin a silver-plated fake or not, in spite of being in a holder?

This looks like it is the same coin but before slabbing:
https://www.m-dv.ru/catalog/p,130165/image.html

Check out the pitted areas on the obverse at 9 o'clock at the "II" in "Nikolai II" and the numerous areas of rim damage.

to the CCF!

The coin is stated as having "Environmental Damage" - I suspect the pitting on the coin you are calling "silver plating that is wearing off" - is due to the ED.

Thanks to everyone for looking and for your replies!

After I saw this coin, I have been reading up on different kinds of silver-plating and other methods of "silvering" coins, even dating back to ancient Rome and earlier (see https://www.forumancientcoins.com/d...fourree.html for some fantastic examples of ancient fourree coins).

What stands out here is the genuine quality of the design and striking pattern. It would of course be VERY helpful to see the edge on this coin. Although the edge is visible with the newer slab types, it is practically impossible to take pictures of it once it is in the holder. Also, things like weighing the coin become difficult without knowing how much the empty slab would weigh.

Since we can assume that the coin was slabbed some time after 2015, they must have been able to do XRF scans ... the weight alone might not reveal whether the core of the metal is silver or not; however, it would have to be extremely difficult to achieve the proper density (e.g. by using an alloy of copper and some heavier metal like lead) and exact dimensions of the coin if it were cast and then silver-plated, due to shrinkage, etc.

I am going to assume that this coin was subjected to all of the tests available at the time of slabbing, knowing how exceedingly rare these are, and that the coin passed these tests. At least I hope so!

So now I am trying to figure out what kind of "environmental damage" might cause such pitting and flaking? Would overdipping cause this?

(EDIT: The auction house (F.R. Künker #258, lot 1051 - you can download the auction catalog as a PDF from https://www.archive.org), who sold this coin before it was slabbed, mentioned in the description "corrosion damage" and condition: "Almost uncirculated, struck from proof dies" - "Min. Korrosionsspuren, sonst vorzüglich/Stempelglanz von polierten Stempeln").

There was also at least one 50 k. 1903 sold, graded by PCGS (possibly later?):
https://www.m-dv.ru/en/catalog/p,244385/image.html

A mintage of 19? Someone will have to do research in mint records to find what was struck. It was not uncommon for the era to strike gold or silver plated coins as tests. And a low mintage may mean that.

But if you got to 19 from counting Encased Coins then you must be undercounting. Few people want their coins in plastic bricks. The mintage must have been higher.

Regardless, if it was struck in very low numbers then understanding why the metal has those flaws requires research about how the very small run was struck.