The secret lies in their ancient and careful blend of no more than six high quality, flavorful and unique grape varietals. Cabernet Sauvignon, Merlot, Petit Verdot, Cabernet Franc, Malbec and Carmnere are all permitted for usage in the production of Bordeaux wines, and the winery carefully considers how to balance the fine points of one varietal against another. Most commonly, Cabernet Sauvignon is used as the main grape varietal, usually with vintners making wines containing upwards of 60% Cabernet Sauvignon grape juices. This varietal lends its big, spicy, fruity flavors and astringent, tannin-heavy character to the mix.