"Slate is another heavyweight roofing material, weighing typically seven-to-eight pounds a square foot. For a smooth look, slate tiles can be sawn to shape on all sides. For more texture, as shown in this roof, the manufacturer shapes the front face by splitting a piece from a larger block, revealing what were once layers of silt. The textured edges of these tiles result from scratching a line on the back, then snapping the sides apart. " - " This Old House .com "
Any of you slate roofers ever try that method???