Is it really all that difficult to counterfeit gold? Couldn't Russia make their gold appear identical to, say, Swiss gold? Unrelated, but I'd like to see an Oc

Is it really all that difficult to counterfeit gold? Couldn't Russia make their gold appear identical to, say, Swiss gold? Unrelated, but I'd like to see an Oceans 14 where with fake accents, disguises and distraction our heros cleverly swindle all of Russia's gold to Ukraine's new offshore depositories in every NATO country.