50 year old blended whisky is a blend of both malt and grain whiskies, the youngest of which must have been aged for at least 50 years. The reason for doing this is to combine the best characteristics of both styles. Malt whisky is used because it is full of flavour and depth, and grain whisky because it can be produced inexpensively and far more efficiently. The master blender's art is using the grain whisky to provide the body of the whisky whilst keeping the final cost down, with malt whisky to bring complexity. 50 year old blended whiskies are very rarely seen. They are, however, very good presents, especially for the big 50th birthday or wedding anniversary.