The online promotion requires entrants to virtually ‘knock on the cask’ – a link to the ritual practised by Jura islanders of knocking on wood prior to drinking a dram.

For every ‘knock’ by an entrant, the price of the cask drops £1 from its £10,000 starting point, while the eventual winner is chosen by random at the end of the eight-week promotion.

The whisky, which has been matured in American white oak and Oloroso sherry casks, will remain on the island to age.

The winner of the promotion will receive “a handful of cases” a year, with the cask expected to yield about 100 bottles in total.

According to Jura, the sherry wood cask acts as a “silk coat” around the flavours of citrus fruits, crushed almonds, violets and walnuts.

Willie Cochrane, distillery manager, said: "This is a once in a lifetime chance for real whisky lovers to own a truly unique single malt from the Isle of Jura.

“The best thing about it is that every year the whisky will mature and change in flavour, due to its longer maturation in the Oloroso sherry butt."