Diamond Creek founder, Al Brounstein, has died aged 86 from complications of Parkinson's disease, a winery spokeswoman told the Associated Press (AP).
Brounstein made only Napa Valley Cabernet Sauvignons and kept grapes from each of his four vineyards separate, in his attempts to promote terroir at Diamond Creek, one of California's first boutique wineries.
According to AP, Brounstein graduated from the University of Minnesota before taking an extension course in wine appreciation at the University of California, Los Angeles and buying the land that would become Diamond Creek Vineyards in 1967.