ProStone Granite Share: Contractors: Specialized ProStone Granite Visit Website 312 Dougherty St Greensboro, NC 27406 (336)574-2755 About Map About Welcome to Prostone Inc where customer satisfaction, and everyday low prices are our number one priority! Prostone has built its reputation for excellent value in Granite Countertops and Solid Wood C What's Nearby? Distance: 5 10 15 20 25 50 mi.