The Palomino grapes are fermented into a dry base wine before being fortified to around 15% and entering the Solera system. A layer of flor yeast develops on the surface of the wine, protecting it from oxygen and allowing the wine to age biologically. Later, the wine is re-fortified to 17.5% - this extra alcohol kills the flor and the wine becomes exposed to oxygen, allowing it to develop complex notes of dried fruits and roasted nuts. The wine ages for an average of nine years, and is sweetened with a small proportion of PX wine to add richness and weight.