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Does someone know how to tell is this coin deliberately blanked from the back or might be factory error? Written on the coin in Russian: чистаго серебра 4 золотн 21 доля Similar coin with both sides: https://www.raritetus.ru/stoimost-monet/carskie-monety/aleksandr-i/serebro/1-rubl-1810-spb-fg-11179/ My coin:

Witch one would you choose for your first coin? Looking for a rare item rather than just a bullion price. What do you guys think? 1. 100€ Gold coin centenary of the republic of Estonia 1918-2018 100€ Gold Coin 1918-2019 Centenary 2. Gold and Silver coin set Gold and Silver Set 1918-2018