To begin the marrying stage – a significantly time-consuming element of the whisky-making approach adopted by The Macallan – most of the precious spirit from the 27 casks was combined and then filled into nine marrying casks at the customary marrying strength. But the instinct of the Master Whisky Maker led to a tenth cask being filled and laid back down. Already matured for three decades, the whisky in this refill butt was kept at its natural strength.
When it reached 35 years of age in 2011 it was assessed again, and a conscious decision was made to allow the whisky to continue to mature and develop character. Finally, at 40 years of age, the time had come. This additional decade of careful maturation through to 2016 has produced a superlative and distinct single malt to add to the collection of rich, mature expressions from The Macallan. The resulting whisky, which is only the second ever non-vintage release of a 40 years old expression, is definitively The Macallan."