 The AOC regulations also allow up to 15 per cent total of Chardonnay, Pinot blanc and Pinot gris as accessory grapes, but this is practically never used for any Burgundy Grand Cru vineyard.The allowed base yield is 35 hectoliter per hectare, a minimum planting density of 9,000 vines per hectare is required as well as a minimum grape maturity of 11.5 per cent potential alcohol.Of the producers in Chambertin, the wines of Domaine Armand Rousseau generally command the highest prices.