Asphalt or Bitumen is a sticky, black and highly viscous liquid or semi-solid form of petroleum. It may be found in natural deposits or may be a refined product. Geologists often prefer the term bitumen. Common usage often refers to various forms of asphalt/bitumen as “tar”, such as at the La Brea Tar Pits. Naturally occurring asphalt/bitumen is sometimes specified by the term “crude bitumen”. Its viscosity is similar to that of cold molasses while the material obtained from the fractional distillation of crude oil boiling at 525 °C (977 °F) is sometimes referred to as “refined bitumen”.