The Macallan Rare CaskMacallan Master Blender Bob Dalgarno selected the barrels that go into Rare Cask from mostly first fill sherry casks that have been maturing at the distillery. Of more than 1000 barrels, aged in " the industry's finest most exclusive and expensive casks," only 1% of the whiskies made the cut and were chosen for their color and depth of flavor. The bottles are presented in a swank gatefold box.