  Crushed stone, for example, has a density of 100 pounds per cubic foot (lb/ft3), which is 1600 kilograms per cubic meter (kg/m3), which is 1.6 metric tons per cubic meter. Packed earth is about 95 lb/ft3, or 1520 kg/m3.
Harvard Business Review. Harvard Business Review. The Harvard Business Review (HBR) is a general management magazine published by Harvard Business Publishing, a wholly owned subsidiary of Harvard University. It is published 6 times a year and is headquartered in Brighton, Massachusetts.
Hydrocarbon gas liquids (HGL), the third most-used category of petroleum, include propane, ethane, butane, and other hydrocarbon gas liquids that are produced at natural gas processing plants and oil refineries. HGL consumption in 2014 was about 2.4 million b/d.