Most Scotch distilleries bank on the fact that some of their oldest whiskies have remained in the same cellar from Day One.
Not Speyside-based whisky- maker The Glenrothes. Its Single Cask 1968, one of its oldest whiskies released in the past decade, has been transferred from one warehouse to another across Scotland under the charge of various owners.
The cask, which was filled in November 1968, was first bought from The Glenrothes by American whisky dealer and collector Abe Rosenburg.
The ownership of the cask collection was transferred to whisky company Duncan Taylor in Glasgow, Scotland, after he died and the casks were kept in its warehouse for more than two decades.
Five years ago, Mr Ronnie Cox, The Glenrothes' brand heritage director, received a tip-off about this batch of old casks.
The 61-year-old Scotsman was initially sceptical about the discovery. He recalls: "I didn't think that they would be good enough as they were left in someone else's warehouse for so long.
"Some of the whiskies in that collection had became too woody with age and had poor alcoholic strength, but the 1968 whisky tastes quite fresh for its age."
He also uncovered some gems from this unexpected find. On top of the 1968 cask, he also picked two other casks that were filled in 1969 and 1970. Bottles from these three casks are now part of The Glenrothes Extraordinary Cask Collection.
Mr Cox was in town recently to launch The Glenrothes 1968, which is the last of the trio to be introduced here. The 1969 and 1970 whiskies were launched here over the past three years.
The second-fill bourbonseasoned American white oak hogshead cask yielded 145 bottles of the 1968 whisky. Only six bottles are for sale here. Each 700ml crystal decanter, which comes with an individualised polished brass plaque that has the bottle number and year of distillation engraved on it, costs $11,200. They can be bought from alcohol company Edrington here.
The gold-hued whisky has a nose of rose petals, canned peaches, apricots, Mirabelle plums and, oddly enough, beeswax polish and candle. The no-chill filtered tipple tastes of mascarpone with orange blossom, white pepper and Turkish delight, on top of its signature creamy texture.
Mr Cox says the key to the whisky's elegant taste lies in ageing it in a second-fill cask. "It is like infusing a tea bag in hot water. The first round is very strong, second round is just right, but flavours from the third round are not too ideal."
He reveals his tip on spotting whiskies that have reached their peak of maturity - rub some drops of whisky on the back of your hand, wait for the alcohol and water to evaporate and sniff the characteristic smells of the whisky.
He says: "If it smells grassy and leafy, it has not been matured. If it has notes of chocolate, leather, dried fruits and wood, it would mean that it has been in a cask for a long period of time."
He says that the trio of whiskies in the Extraordinary Cask Collection have a more fruity taste reminiscent of cooked oranges and dried fruit, coupled with a vanilla-like creaminess, compared with younger single-cask releases.
Mr Cox is a seventh-generation member of a whisky-distilling family, which owned the now- defunct distillery Cardow Distillery (now known as Cardhu Distillery and run by British alcohol giant Diageo) in Speyside.
Whisky is such a big part of his life that he speaks of it as though it is human during the hour-long interview.
When asked about the difference among the three bottlings in the Extraordinary Cask Collection, he says with a chuckle: "All three are children who have attended university and have nuanced differences in personalities. For example, the 1968 can be found in a formal dinner jacket, while the 1970 wears a casual and fun velvet jacket."