The world's most expensive whisky shot. [Screenshot from BBC.com]

GENEVA - The world's most expensive whisky shot, bought in August for $10,000 at a hotel in the exclusive St Moritz resort in Switzerland, was shown on Thursday to be fake.

After being submitted to laboratory tests by Scottish whisky experts and at Oxford University, the liquor was found not have been what it claimed to be -- an 1878 bottle of Macallan Single Malt, Swissinfo, the website of the Swiss national broadcaster reported.

The Waldhaus Am See Hotel has reimbursed the Chinese drinker who bought the tipple, as it had promised to do if the drop was found to be a fake.

Carbon dating found that there is a "95 percent probability that the liquid was created between 1970 and 1972," according to a press statement sent by the hotel to Swissinfo.

Moreover, the whisky may not have even been a single malt. Scotch analysts said it was more likely a blended Scotch, of 60 percent malt and 40 percent grain.

The hotel said it has taken responsibility for the sale and reimbursed the buyer in full.

Hotel owner Sandro Bernasconi traveled to China to personally apologize and hand over the check to the young whisky aficionado.

"The result has been a big shock to the system," Bernasconi said in the statement. "We are delighted to have repaid our customer in full as a gesture of goodwill."

The bottle had been bought by Bernasconi's father Claudio 25 years ago for a "five-figure sum".

However, soon after the pricy sale, experts questioned the authenticity of the whisky, and the hotel itself sent the bottle for testing in the UK.

"When it comes to selling our customers some of the world's rarest and oldest whiskies, we felt it was our duty to ensure that our stock is 100 percent authentic and the real deal," Bernasconi said.