DAHLONEGA — A woman with a weathered face, silver hair piled atop her head, sits on a rustic porch admiring a patchwork quilt.Behind her, hazy blue mountains and a stream that winds its way between Dahlonega landmarks form the backdrop of a mural depicting the history and culture of Appalachia. The mural will be unveiled Saturday at the entrance of North Georgia College & State University’s Hansford Hall, which houses the Department of Visual Arts. From concept to completion, the project has been a year in the making and the art students who took part learned about Appalachia and collaboration.