Abacus, ZD Wines’ legendary Napa Valley Cabernet Sauvignon, is a multi-vintage blend that artfully expresses the depth and complexity of a well-aged wine, infused with a touch of forward fruit and the intensity of a younger wine. It is defined by ZD Wines’ Reserve Cabernet Sauvignon, which has been produced every year since 1992. The wine is aged for three years in the barrel which allows access to the young reserve wines as a blending component to Abacus. Hence, there is always a component of young, fruit forward wine available to infuse into the ever-developing Abacus solera. The current bottling of Abacus XXVIII is a masterful blend of 34 vintages of ZD’s Reserve Cabernet Sauvignon (1992-2025).

How to Read an Abacus

The Abacus, an ancient counting device, was chosen as this wine’s namesake. The wine is a “solera style” multiple vintage blend of every ZD Reserve Cabernet Sauvignon ever produced. The medallion attached to each bottle depicts an abacus that identifies the first and last vintages in the wine.

The traditional abacus is divided into two parts, with five beads in the lower section and two in the upper section. Each lower bead is worth one unit, and each upper bead is worth five units. The beads are only counted when they are pushed against the crossbar dividing the abacus into its two sections. To read the abacus, which depicts the first and last vintages in the Twenty-Eighth Bottling of ZD’s Abacus (1992-2025), add the value of the beads above the crossbar to the value below for each row. There is a zero row separating the two dates.