[DOC] [TLE] Lignite - Wikipedia [PAR] Lignite, often referred to as brown coal, is a soft brown combustible sedimentary 
rock formed from naturally compressed peat. It is considered the lowest rank of 
coal due to its relatively low heat content. It has a carbon content around 6070 
percent. .... Jet is a hardened, gem-like form of lignite used in various types of 
jewelry. [DOC] [TLE] Coal: Anthracite, Bituminous, Coke, Pictures, Formation, Uses [PAR] Coal is a biological sedimentary rock that forms from plant debris. ... plant types, 
and plant productivity can vary in different parts of the swamp. ... It has a carbon 
content of less than 60% on a dry ash-free basis. Lignite ... are subdivided into 
low-volatile bituminous, medium-volatile bituminous, and high-volatile 
bituminous. [DOC] [TLE] How Coal Works | Union of Concerned Scientists [PAR] The carbon content is low also, around 40 percent. Lignite is typically used only 
when higher grades of coal are not available or ... In the West, where coal seams 
are not far underground, rocks called "clinker" are found on the surface .... 
Another type of coal plant uses "fluidized bed combustion" instead of a standard 
furnace... [DOC] [TLE] coal characteristics - Purdue University [PAR] As geological processes apply pressure to peat ... NS for high-grade Anthracite ... 
Anthracite coal is a dense, hard rock with a jet- ... Sub-bituminous coal contains 
less carbon, more ... Each type of coal has a certain set of physical ... methane, 
that contain only carbon & hydrogen ..... from low-ash, low-sulfur bituminous coal. [DOC] [TLE] lignite | coal | Britannica.com [PAR] Lignite contains about 60 to 70 percent carbon (on a dry, ash-free basis) and has 
... the surface and are of great thickness, sometimes greater than 30 m (about 
100 ... This low-grade, waterlogged fuel can be worked economically in vast 
open .... From very early times glass has been used for various kinds of vessels, 
and in... [DOC] [TLE] Where does coal come from? | MNN - Mother Nature Network [PAR] Aug 4, 2009 ... The organic rock is so potent and plentiful, in fact, that U.S. coal .... Lignite is low-
grade coal to begin with, containing only about 30 percent carbon ... hardest and 
usually oldest type, with a carbon content of 86 to 97 percent. [DOC] [TLE] Lignite and climate change - Parliamentary Commissioner for the ... [PAR] our greenhouse gas emissions are on track to be 30% above the 1990 level by 
2020. ... Lignite, or brown coal, is a low grade form of coal containing relatively 
high ... The Emissions Trading Scheme (ETS) is the only significant mechanism 
currently ..... If there is an unbroken seal of impermeable rock on top, the carbon. [DOC] [TLE] CO 0009 - Eskom [PAR] Coal is a combustible, sedimentary, organic rock formed from ancient vegetation, 
... was converted into lignite or brown coal  a coal type with low organic 'maturity'
. ... by high moisture levels and a low carbon content, and hence a low energy 
content. ... Brown coals or lignite have a high oxygen content (up to 30 percent), a
. [DOC] [TLE] Deposition and Sedimentary Rock Formation - MountainNature.com [PAR] ->Landform by Type ... Of this, approximately 50% are shales, 30% sandstone 
and 20% limestone. ... as the remains of other older rocks that were eroded away, 
only to have their individual ... In many area's, peat is used as a low grade fuel 
source. ... the percentage of carbon, and begins the transformation from peat to 
coal. [DOC] [TLE] Can Coal Ever Be Clean? - National Geographic Magazine [PAR] It's whether coal can ever be clean enoughto prevent not only local .... Other 
types of rock also have potential as carbon lockers. ... one that could eat up as 
much as 30 percent of the total energy output of a coal plant that was capturing 
all its carbon. .... Company leaders say the plant's use of lignite

Question: Lignite, a low-grade type of this rock, is only about 30 percent carbon
Answer: coal