Fossil fuel embedded energy is still photosynthetic in origin. Terrestrial plants, on the other hand, tended to form coal and methane. Many of the coal fields date to the Carboniferous period of Earth's history. Terrestrial plants also form type III kerogen, a source of natural gas. There is a wide range of organic, or hydrocarbon, compounds in any given fuel mixture. The specific mixture of hydrocarbons gives a fuel its characteristic properties, such as boiling point, melting point, density, viscosity, etc. Some fuels like natural gas, for instance, contain only very low boiling, gaseous components. Others such as gasoline or diesel contain
Pakistan Nuclear Power Fuel Complex late 2010. Cost of the Pakistan Nuclear Power Fuel Complex (PNPFC) was originally estimated at Rs. 51.298 billion. The complex will fabricate fuel for local nuclear power plants, in particular for the reactors at Chashma Nuclear Power Plant. The Nuclear Power Fuel Facility comprises Chemical Processing Plants, Nuclear reprocessing plant, an Enrichment Plant, a Seamless Tube Plant; a Fuel Fabrication Plant; and a Nuclear Fuel Testing Facility. For information on Pakistani nuclear power reactors, see the articles Chashma Nuclear Power Plant and Karachi Nuclear Power Plant. Pakistan Nuclear Power Fuel Complex The Pakistan Nuclear Power Fuel Complex (PNPFC), also known