Part of the Bushmills causeway collection The 2008 Muscatel Cask is a limited edition rare cask finished, cask strength (56.4% ABV) and non chill filtered Irish single malt. It represents a bold new step for Bushmills. After maturing for almost eight years in oloroso sherry butts and bourbon barrels, Helen Mulholland, Master Blender, finished this whiskey in rare muscatel cask, for a further 4 years.