The lake is mined for asphalt by Lake Asphalt of Trinidad and Tobago. Building materials mainly include travertine, crushed stones, asphalt and asphalt concrete. This makes sandstone a common building and paving material including in asphalt concrete. The core can be of clay, concrete, or asphalt concrete. Today, roadways are primarily asphalt or concrete. When studs come into contact with pavements they abrade the asphalt or concrete surface. The park is made of asphalt and pea gravel. Then they spray or brush a primer layer on the asphalt or concrete surface. Brick surfacing was a good compromise, but even better was asphalt paving. Grass, clay, and hardcourts of concrete or asphalt topped with acrylic are the most common. The runway is asphalt and concrete, x . Some research has indicated a correlation between this adulteration of asphalt and poorer-performing pavement. Despite these difficulties, the waste is used as a filler in asphalt and concrete. A core that is growing in popularity is asphalt concrete. Roofing shingles and roll roofing account for most of the remaining asphalt consumption.