Photomicrograph of a volcanic lithic fragment (sand grain); upper picture is plane-polarized light, bottom picture is cross-polarized light, scale box at left-center is 0.25 millimeter. Volcanic rocks are usually fine-grained or aphanitic to glass in texture. They often contain clasts of other rocks and phenocrysts.
I paid almost $13,000 to have Duration Premium shingles installed on my central Florida home in late 2007. I went with Owens Corning Duration Premium shingles because of their premium quality, their lifetime warranty and their high wind resistance. Within 3 months of the installation, I started having leaks.
Cost. On average, dimensional shingles run around $3-5 per square foot installed, or about 20% more than 3-tab shingles. Designer shingles average $4-$6 per square foot installed. Please note that these are general averages, and do not include tear off of an existing roof.