A "solera style" multiple-vintage blend of every ZD Reserve Cabernet Sauvignon ever produced, which is held in barrel until bottling. The first bottling, with the 1992 - 1998 vintages, was released November 1, 1999. Approximately 15% of the total blend was bottled in distinctive custom bottles, totaling 200 cases. The remainder was returned to barrel to await the next infusion of youthful fruit. Prior to the second bottling, the 1999 Reserve Cabernet Sauvignon was added to the blend. This is the ongoing cycle of the ever-evolving solera; each year Abacus will increase by one vintage, gaining more and more complexity.