Editing Anthracite

{{Short description|Hard, compact variety of coal}}
{{Redirect|Hard coal|the coal known in Turkey as hard coal|Bituminous coal}}
{{about|the compact variety of coal|the Netflix television series|Anthracite (TV series){{!}}''Anthracite'' (TV series)}}
{{Infobox rock
|name = Anthracite coal
|alternative_name = Black coal, hard coal, stone coal, blind coal, Kilkenny coal, crow coal, craw coal, black diamond
|type = Metamorphic
|image = Anthracite chunk.JPG
|image_size = 250px
|image_alt = Anthracite coal
|image_caption = Anthracite coal
|composition = 86–97% [[carbon]]<ref name="coalex">{{cite web |url=https://www.eia.gov/energyexplained/coal/ |title=Coal explained |publisher=U.S. Energy Information Administration |access-date=16 January 2022 |url-status=live|archive-url=https://web.archive.org/web/20190829125707/https://www.eia.gov/energyexplained/coal/ |archive-date=2019-08-29 }}</ref>
}}
'''Anthracite''', also known as '''hard coal''' and '''black coal''', is a hard, compact variety of [[coal]] that has a [[lustre (mineralogy)#Submetallic lustre|submetallic lustre]]. It has the highest [[carbon]] content, the fewest impurities, and the highest [[energy density]] of all types of coal and is the highest [[Coal analysis#Coal classification by rank|ranking]] of coals.

The [[Coal Region]] of [[Northeastern Pennsylvania]] in the [[United States]] has the largest known deposits of anthracite coal in the world with an estimated reserve of seven billion [[short ton|short tons]].<ref>Carpenito, Thomas (2019) ''"The State of Coal and Renewable Energy in Schuylkill County", https://medium.com/@thomascarpenito3/state-of-coal-and-renewable-energy-in-schuylkill-f8850fec3fa6</ref>{{void|bad link= {{plain link|https://medium.com/@thomascarpenito3/state-of-coal-and-renewable-energy-in-schuylkill-f8850fec3fa6.html/ |Necho Allen}}.}} [[Coal in China|China]] accounts for the majority of global production; other producers include [[Coal in Russia|Russia]], [[Coal in Ukraine|Ukraine]], [[Coal in North Korea|North Korea]], [[Coal in South Africa|South Africa]], [[Coal in Vietnam|Vietnam]], [[Coal in Australia|Australia]], [[Coal in Canada|Canada]], and the [[Coal mining in the United States|United States]]. Total production in 2020 was 615 million tons.<ref name="eia.gov">{{cite web |url=http://www.eia.gov/cfapps/ipdbproject/iedindex3.cfm?tid=1&pid=11&aid=1&cid=regions&syid=2006&eyid=2010&unit=TST |title=International Energy Statistics |publisher=[[Energy Information Administration]]}}</ref>

Anthracite is the most [[metamorphism|metamorphosed]] type of coal, but still represents low-grade  metamorphism,{{refn |For example, anthracite of the Narragansett Basin in [[Rhode Island]] is of [[greenschist]] [[metamorphic facies]] ([[muscovite]]-[[Chlorite group|chlorite]] sub-facies).<ref name="RhodI_1958">{{cite journal | last1=Quinn | first1=A.W. | last2=Glass | first2=H.D. | title=Rank of Coal and Metamorphic Grade of Rocks of the Narragansett Basin of Rhode Island | journal=[[Economic Geology (journal)|Economic Geology]] | volume=53 | issue=5 | date=1958 | pages=563–576 | doi=10.2113/gsecongeo.53.5.563| bibcode=1958EcGeo..53..563Q }}</ref>|group=lower-alpha}} in which the carbon content is between 86% and 97%.<ref name="coalex"/><ref>{{cite web |url=http://www.faculty.uaf.edu/ffrg/min454/Handout2_UMM.doc |title=MIN 454: Underground Mining Methods handout; from course at the University of Alaska Fairbanks| access-date= 2009-05-05| archive-url= https://web.archive.org/web/20090326053910/http://www.faculty.uaf.edu/ffrg/min454/Handout2_UMM.doc| archive-date= 26 March 2009| url-status= dead}}</ref><ref>{{cite book| title = Coal Mining Technology: Theory and Practice| first= R. |last=Stefanenko| publisher = Society for Mining Metallurgy | year = 1983| isbn = 0-89520-404-5}}</ref> The term is applied to those varieties of coal which do not give off [[coal tar|tarry]] or other [[hydrocarbon]] vapours when heated below their point of [[Combustion|ignition]].{{sfn|Bauerman|1911|p=105}} Anthracite is difficult to ignite, and burns with a short, blue, and smokeless flame.

Anthracite is categorized into several grades. Standard grade is used predominantly in power generation, and high grade (HG) and ultra high grade (UHG), are used predominantly in the [[metallurgy]] sector. Anthracite accounts for about 1% of global coal reserves,<ref>{{cite web |url=http://www.worldcoal.org/bin/pdf/original_pdf_file/coal_resource_overview_of_coal_report(03_06_2009).pdf |publisher=World Coal Institute |title=The Coal Resource: A Comprehensive Overview of Coal |archive-url=https://web.archive.org/web/20091015130721/http://www.worldcoal.org/bin/pdf/original_pdf_file/coal_resource_overview_of_coal_report%2803_06_2009%29.pdf |archive-date=15 October 2009 }}</ref> and is mined in only a few countries around the world.

{{anchor|culm|Culm|Name|Terminology|Etymology}}

==Names==
[[File:Coal waste pile west of Trevorton, Pennsylvania far shot 2.JPG|thumb|An anthracite pile in [[Trevorton, Pennsylvania]]]]
[[File:Lackawanna Coal Mine car, Nov 2014.jpg|thumb|A coal mine car used to enter and exit the [[Lackawanna Coal Mine Tour]], where Lackawanna Coal Mine once operated in [[Scranton, Pennsylvania]]]]
Anthracite derives from the [[ancient Greek|Greek]] ''anthrakítēs'' ({{lang|grc|ἀνθρακίτης}}), literally "coal-like".<ref name=oed>{{cite encyclopedia |title=anthracite |dictionary=The Oxford English Dictionary |edition=2nd |date=1989 |publisher=Oxford University Press |access-date=2010-06-26 |url=http://dictionary.oed.com/cgi/entry/50009392}}</ref> Other terms which refer to anthracite are '''black coal''', '''hard coal''', '''stone coal''',{{sfnp|''Encyclopædia Britannica''|1878}}{{refn|Not to be confused with the [[German language|German]] ''Steinkohle''{{sfn|Bauerman|1911|p=105}} or [[Dutch language|Dutch]] ''steenkool'' which are broader terms meaning all varieties of coal of a stonelike [[hardness]] and appearance, like bituminous coal and often anthracite as well, as opposed to lignite, which is softer.}} '''dark coal''', '''coffee coal''', '''blind coal''' (in Scotland),{{sfn|Bauerman|1911|p=105}} '''Kilkenny coal''' (in Ireland),{{sfnp|''Encyclopædia Britannica''|1878}} '''crow coal''' or '''craw coal''', and '''black diamond'''. '''"Blue Coal"''' is the term for a once-popular and trademarked brand of anthracite, mined by the Glen Alden Coal Company in [[Pennsylvania]], and sprayed with a blue dye at the mine before shipping to its [[Northeastern United States|Northeastern U.S.]] markets to distinguish it from its competitors.<ref>{{cite web |title=Huber Coal Breaker, 101 South Main Street, Ashley, Luzerne County, PA |url=https://www.loc.gov/resource/hhh.pa2251.sheet/?sp=1 |publisher=Library of Congress |access-date=December 14, 2021 |page=1 |date=1991}}</ref> 

Culm has different meanings in [[British English|British]] and [[American English]]. In British English, culm is the imperfect anthracite, located predominantly north [[Devon]] and [[Cornwall]], which was used as a [[pigment]]. The term is also used to refer to some carboniferous [[Stratum|rock strata]] found in both Britain and in the [[Rhenish]] hill countries, also known as the [[Culm Measures]].{{sfn|Bauerman|1911|p=105}} In Britain, it may also refer to coal exported from Britain during the 19th century.{{sfnp|''Encyclopædia Britannica''|1878}}  In American English, "culm" refers to the waste or slack from anthracite mining,{{sfn|Bauerman|1911|p=105}} mostly dust and small pieces not suitable for use in home furnaces.

== Properties ==
[[File:Ibbenbueren Anthracite.JPG|thumb|Anthracite coal from [[Ibbenbüren, Germany]]]]
[[File:Anthracite coal (Photo by John Mortimore).jpg|thumb|Anthracite from [[Bay City, Michigan]]]]
{{Coal sidebar|state=collapsed}}
Anthracite is similar in appearance to the [[mineraloid]] [[jet (lignite)|jet]] and is sometimes used as a jet imitation.

Anthracite differs from ordinary [[bituminous coal]] by its greater hardness (2.75–3 on the [[Mohs scale of mineral hardness|Mohs scale]]),<ref name="USGSHardness">{{cite book | title=Mineral Resources of the Appalachian Region; USGS Professional Paper 580 | publisher=[[USGS]] | author=US Geological Survey and US Department of Mines | year=1968 | page=126}}</ref> its higher [[relative density]] of 1.3–1.4, and luster, which is often semi-metallic with a mildly green reflection. It contains a high percentage of fixed carbon and a low percentage of [[Volatility (chemistry)|volatile]] matter. It is also free from included soft or fibrous notches and does not soil the fingers when rubbed.{{sfn|Bauerman|1911|p=105}} Anthracitization is the transformation of bituminous coal into anthracite.

The moisture content of fresh-mined anthracite generally is less than 15 percent. The heat content of anthracite ranges from 26 to 33 MJ/kg (22 to 28 million [[British thermal unit|Btu]]/[[short ton]]) on a moist, mineral-matter-free basis. The heat content of anthracite coal consumed in the United States averages 29 MJ/kg (25 million Btu/ton), on the as-received basis, containing both inherent moisture and mineral matter.

Since the 1980s, anthracite refuse or mine waste has been used for [[fossil fuel power plant|coal power generation]] in a form of [[recycling]]. The practice known as [[mine reclamation|reclamation]] is being applied to culm piles antedating laws requiring mine owners to restore lands to their approximate original condition.

Chemically, anthracite may be considered as a transition stage between ordinary bituminous coal and [[graphite]], produced by the more or less complete elimination of the volatile constituents of the former, and it is found most abundantly in areas that have been subjected to considerable stresses and pressures, such as the flanks of great mountain ranges.{{sfn|Bauerman|1911|p=105}} Anthracite is associated with strongly deformed [[sedimentary rock]]s that were subjected to higher pressures and temperatures (but short of metamorphic conditions) just as bituminous coal is generally associated with less deformed or flat-lying sedimentary rocks. The compressed layers of anthracite that are deep mined in the folded [[Ridge-and-Valley Appalachians|Ridge and Valley Province]] of the [[Appalachian Mountains]] of the [[Coal Region]] of East-central [[Pennsylvania]] are extensions of the same layers of bituminous coal that are mined on the generally flat lying and undeformed sedimentary rocks further west on the [[Allegheny Plateau]] of [[Kentucky]] and [[West Virginia]], Eastern [[Ohio]], and [[Western Pennsylvania]].

In the same way the anthracite region of [[South Wales]] is confined to the contorted portion west of [[Swansea]] and [[Llanelli]], the central and eastern portions producing [[steam coal]], [[coking coal]] and domestic house coals.{{sfn|Bauerman|1911|pp=105-106}}

Anthracite shows some alteration by the development of secondary divisional planes and fissures so that the original stratification lines are not always easily seen. The thermal conductivity is also higher; a lump of anthracite feels perceptibly colder when held in the warm hand than a similar lump of bituminous coal at the same temperature.{{sfn|Bauerman|1911|p=105}}

Anthracite has a history of use in [[blast furnace]]s for iron smelting; however, it lacked the pore space of metallurgical [[coke (fuel)|coke]], which eventually replaced anthracite.<ref>{{Harvnb|Rosenberg|1982|pp=89}}</ref>

== History of mining and use ==
[[File:Coal plant, Madrid c. 1935.jpg|thumb|An anthracite coal breaker and power house buildings in [[Madrid, New Mexico]], {{circa|1935}}]]
[[File:Working together for Victory. Anthracite is a "fighting fuel." America needs it now. - NARA - 534850.jpg|thumb|"Anthracite is a 'fighting fuel'", a [[World War II]] poster promoting anthracite, which was used extensively in military production]]
In southwest [[Wales]], anthracite has been burned as a domestic fuel since at least medieval times,<ref>Owen, George, ''The Description of Pembrokeshire'', Dillwyn Miles (Ed), Gomer Press, Llandysul, 1994, {{ISBN|1-85902-120-4}}, pp. 60, 69–70, 90–95, 139, 255</ref> when it was mined near [[Saundersfoot]]. More recently, large-scale mining of anthracite took place across the western part of the [[South Wales Coalfield]] until the late 20th century.

In the United States, anthracite coal history began in 1790 in [[Pottsville, Pennsylvania]], with the discovery of coal made by the hunter Necho Allen in what is now known as the [[Coal Region]]. Legend has it that Allen fell asleep at the base of [[Broad Mountain (Schuylkill Valley)|Broad Mountain]] and woke to the sight of a large fire because his campfire had ignited an outcrop of anthracite coal.<ref name= "Pottsville">{{cite web |author=<!-- not stated --> |date= 31 Jan 2001| title= History |url= https://www.pottsvillepa.gov/html/history.htm |website= City of Pottsville, Pennsylvania - Official Website |location= Pottsville, Pennsylvania |publisher= City of Pottsville |access-date= 19 February 2025}}</ref>

By the late 18th century, it was known in the United States that anthracite could be burnt, but the techniques required to do so were unknown. Anthracite differs from wood and bituminous coal in that it has a higher ignition temperature and needs a fresh air draft from the bottom to burn. Several claims are made about who "first" burnt anthracite coal in the United States around this time, and all such claims originate from Pennsylvania. The city of Pottsville, Pennsylvania claims that their town was founded around an anthracite-fired [[blast furnace|iron furnace]] purchased by [[John_Potts_(Pennsylvanian)|John Potts]] in 1806, which was built on the [[Schuylkill River]] in 1795.<ref name= "Pottsville"/> Pennsylvanian Charles V. Hagner recalls in his 1869 book that an unnamed employee of [[Josiah White]] and [[Erskine Hazard]] accidentally burnt anthracite in their rolling mill at the [[Schuylkill River|Falls of the Schuylkill River]] (after much failed experimentation with burning anthracite)<ref name="Hagner">{{cite book |last= Hagner |first= Charles V. |url= https://archive.org/details/earlyhistoryoffa00hagn |title= Early history of the Falls of Schuylkill, Manayunk, Schuylkill and Lehigh navigation companies, Fairmount waterworks, etc. |pages=42-44 |publisher= Caxton, Remsen, and Haffelfinger |location= 819 & 821 Market Street, Philadelphia, USA |date= 1869 |access-date= February 19, 2025}}</ref> at some point between 1812<ref name=Fritts>{{cite book |last=Frittz |first=Peter |date=1877 |title=History of Northhampton County, Pennsylvania, Illustrated |chapter=XXXIV |page=85 |url= http://files.usgwarchives.net/pa/northampton/history/local/davis/davis10.txt |access-date= 19 February 2025}}</ref> and 1815.<ref name="Hagner"/> Judge [[Jesse Fell]] is claimed to be the first person to burn anthracite for the purposes of residential heating in the USA in [[Wilkes-Barre, Pennsylvania]] on 11 February 1808. Judge Fell used an open grate in his fireplace to burn anthracite, as an experiment to prove that it was a viable residential heating fuel.<ref name=TimesLeader>{{cite news |last= Lewis |first= Edward |date= 6 February 2022 |title= Look Back: Stone coal first burned for domestic use in 1808 |url= https://www.timesleader.com/news/1538486/look-back-stone-coal-first-burned-for-domestic-use-in-1808 |work= Times Leader |location= Pennsylvania |publisher= Times Leader Media Group |access-date= 19 February 2025}}</ref>

In spring 1808, John and Abijah Smith shipped the first commercially mined load of anthracite down the [[Susquehanna River]] from Plymouth, Pennsylvania, marking the birth of commercial anthracite mining in the United States. From that first mine, production rose to an all-time high of over 100 million tons in 1917.{{Citation needed|date=May 2012}}

The difficulty of igniting anthracite inhibited its early use, especially in [[blast furnace]]s for smelting iron. With the development of the [[hot blast]] in 1828, which used waste heat to preheat combustion air, anthracite became a preferred fuel, accounting for 45% of US pig iron production within 15 years.<ref>{{cite book
| title = Inside the Black Box: Technology and Economics
| last = Rosenberg
| first = Nathan
| year = 1982
| publisher = [[Cambridge University Press]]
| location = Cambridge, New York
| isbn = 0-521-27367-6
| page = [https://archive.org/details/insideblackboxte00rose/page/88 88]
| url-access = registration
| url = https://archive.org/details/insideblackboxte00rose/page/88
}}</ref>  [[Anthracite iron]] smelting was later displaced by [[coke (fuel)|coke]].

From the late 19th century until the 1950s, anthracite was the most popular fuel for heating homes and other buildings in the northern US, until it was supplanted by oil-burning systems, and more recently natural gas systems. Many large public buildings, such as schools, were heated with anthracite-burning furnaces through the 1980s.

During the [[American Civil War]], Confederate [[Blockade runners of the American Civil War|blockade runners]] used anthracite as a smokeless fuel for their boilers to avoid revealing their position to the blockaders.<ref>{{Cite book |last=Underwood |first=Rodman L. |title=Waters of Discord: The Union Blockade of Texas During the Civil War |publisher=McFarland |page=55 |url=https://books.google.com/books?id=QxywnKkZSlYC&pg=PA55 |isbn=978-0786437764 |date=2008 }}</ref>

The invention of the [[Wootten firebox]] enabled [[steam locomotive|locomotives]] to directly burn anthracite efficiently, particularly waste culm. In the early 20th century US, the [[Delaware, Lackawanna and Western Railroad]] started using only the more expensive anthracite coal in its passenger locomotives, dubbed themselves "The Road of Anthracite", and advertised widely that travelers on their line could make railway journeys without getting their clothing stained with soot. The advertisements featured a white-clad woman named [[Phoebe Snow (character)|Phoebe Snow]] and poems containing lines like "My gown stays white / From morn till night / Upon the road of Anthracite". Similarly, the [[Great Western Railway]] in the UK was able to use its access to anthracite (it dominated the anthracite region) to earn a reputation for efficiency and cleanliness unmatched by other UK companies.

Internal combustion motors driven by the so-called "mixed", "poor", "semi-water" or "[[Dowson gas]]" produced by the [[gasification]] of anthracite with air (and a small proportion of steam) were at one time the most economical method of obtaining power, requiring only {{convert|1|lb/hph|kg/kWh|sigfig=1|lk=on}}, or less. Large quantities of anthracite for power purposes were formerly exported from South Wales to France, Switzerland and parts of Germany.{{sfn|Bauerman|1911|p=106}}

Commercial anthracite mining in [[Wales]] ceased in 2013, although a few large [[open cast]] sites remain, along with some relatively small [[drift mining]] operations.{{Citation needed|date=August 2017}} Commercial anthracite mining is still ongoing{{Cn|date=March 2025|reason=2015 cite not recent enough}} in Pennsylvania; the state produced a "total of 4,614,391 tons of [anthracite] coal, predominately from surface coal mines"<ref name="PACoalHistory">{{cite web |author=<!-- not stated --> |date= 2016 |title= History of Coal Mining in Pennsylvania |url= https://www.pa.gov/agencies/dep/programs-and-services/mining/bureau-of-mining-programs/pa-mining-history.html |website= Official Website of the Commonwealth of Pennsylvania |publisher= Commonwealth of Pennsylvania |access-date= 19 February 2025}}</ref> in 2015.

==Anthracite today==
[[File:Pottsville Maroons self-made trophy.jpg|thumb|An [[American football]] trophy custom-made from anthracite]]
Anthracite generally costs two to six times as much as regular coal. In June 2008, the wholesale cost of anthracite was US$150/[[short ton]],<ref>{{cite news |url=https://www.nytimes.com/2008/06/10/us/10coal.html
|title=King Coal Country Debates a Sacrilege, Gas Heat |first=Ian |last=Urbina|date= June 10, 2008|newspaper=The New York Times|access-date= June 21, 2008}}</ref> falling to $107/ton in 2021; it makes up 1% of U.S. coal production.<ref>{{Cite web |title=Coal prices and outlook - U.S. Energy Information Administration (EIA) |url=https://www.eia.gov/energyexplained/coal/prices-and-outlook.php |access-date=2023-05-13 |website=www.eia.gov}}</ref><!---retail varies widely (ave $250/ton) probably due to shipping--->

The principal use of anthracite today is for a domestic fuel in either hand-fired stoves or automatic stoker furnaces. It delivers high energy per its weight and burns cleanly with little soot, making it ideal for this purpose. Its high value makes it prohibitively expensive for power plant use. Other uses include the fine particles used as filter media, and as an ingredient in [[charcoal]] [[briquettes]]. Anthracite was an authorised fuel<ref>{{cite web|url=http://www.uksmokecontrolareas.co.uk/index.php#auth|title=uksmokecontrolareas.co.uk|url-status=dead|archive-url=https://web.archive.org/web/20090207182227/http://www.uksmokecontrolareas.co.uk/index.php#auth|archive-date=2009-02-07}}</ref> in terms of the United Kingdom's [[Clean Air Act 1993]], meaning that it could be used within a designated Smoke Control Area such as the central London boroughs.

=== Mining ===
China today mines by far the largest share of global anthracite production, accounting for more than three-quarters of global output.<ref name="eia.gov"/> Most Chinese production is of standard-grade anthracite, which is used in power generation.{{Citation needed|date=December 2020}} Increased demand in China has made that country into a net importer of the fuel, mostly from Vietnam, another major producer of anthracite for power generation, although increasing domestic consumption in Vietnam means that exports may be scaled back.<ref name="Petmin Annual Report 2011">[http://www.petmin.co.za/ir/files/reports/ar2011/perf_operations.html Petmin Annual Report 2011] {{webarchive |url=https://web.archive.org/web/20120505094917/http://www.petmin.co.za/ir/files/reports/ar2011/perf_operations.html |date=May 5, 2012 }}</ref>

Current U.S. anthracite production averages around five million tons per year. Of that, about 1.8 million tons were mined in the state of Pennsylvania.<ref>{{cite web|url=http://coaldiver.org/coal-diver/Pennsylvania-Anthracite |title=retrieved January 3, 2011 |publisher=Coaldiver.org |access-date=2018-01-24}}</ref> [[History of anthracite coal mining in Pennsylvania|Mining of anthracite coal]] continues to this day in eastern Pennsylvania, and contributes up to 1% to the gross state product. More than 2,000 people were employed in the mining of anthracite coal in 1995. Most of the mining as of that date involved reclaiming coal from slag heaps (waste piles from past coal mining) at nearby closed mines. Some underground anthracite coal is also being mined.

Countries producing HG and UHG anthracite include Russia and South Africa. HG and UHG anthracite are used as a [[coke (fuel)|coke]] or coal substitute in various [[metallurgical coal]] applications ([[sintering]], [[Pulverized coal injection method|PCI]], direct [[blast furnace|BF]] charge, [[pelletizing]]). It plays an important role in cost reduction in the steel making process and is also used in production of [[ferroalloy]]s, silicomanganese, [[calcium carbide]] and [[silicon carbide]]. South Africa exports lower-quality, higher-ash anthracite to Brazil to be used in steel-making.{{Citation needed|date=May 2015}}

== Sizing and grading ==
[[File:Breaker Boys 1.jpg|thumb|A photograph taken in 1908 by [[Lewis Hine]] of a group of [[breaker boy]]s in [[Pittston, Pennsylvania]]]]
Anthracite is processed into different sizes by what is commonly referred to as a [[Coal breaker|breaker]]. The large coal is raised from the mine and passed through breakers with toothed rolls to reduce the lumps to smaller pieces. The smaller pieces are separated into different sizes by a system of graduated sieves, placed in descending order.{{sfn|Bauerman|1911|p=106}} Sizing is necessary for different types of stoves and furnaces.

Anthracite is classified into three grades, depending on its carbon content. Standard grade is used as a domestic fuel and in industrial power-generation. The rarer higher grades of anthracite are purer – i.e., they have a higher carbon content – and are used in steel-making and other segments of the metallurgical industries. Technical characteristics of the various grades of anthracite are as follows:{{Citation needed|date=April 2012}}

{| class="wikitable"
|-
! !! Standard grade anthracite !! High grade anthracite !! Ultra High grade anthracite !! [[coke (fuel)|Coke]]
|-
| Moisture (maximum) || 15% || 15% || 13% || 5%
|-
| Ash (maximum) || 20% || 15% || 12% || 14%
|-
| Volatiles (maximum) || 10% || 10% || 5% || 2%
|-
| Fixed carbon (minimum) || 73% || 80% || 85% || 84%
|-
| Sulfur (maximum) || 1%|| 1% || 0.6% || 0.8%
|}
Anthracite is divided by size mainly into applications that need lumps (typically larger than 10&nbsp;mm) – various industrial processes where it replaces metallurgical [[coke (fuel)|coke]], and domestic fuel – and those that need fines (less than 10&nbsp;mm), such as sintering and pelletising.<ref name="Petmin Annual Report 2011"/>

The common American classification by size is as follows:{{Citation needed|date=December 2007}}

Lump, steamboat, egg and stove coals, the latter in two or three sizes, all three being above {{frac|1|1|2}}&nbsp;in (38&nbsp;mm) size on round-hole screens.

===High grade===
High grade (HG) and ultra high grade (UHG) anthracite are the highest grades of anthracite coal. They are the purest forms of coal, having the highest degree of coalification, the highest carbon count and energy content and the fewest impurities (moisture, ash and volatiles).

High grade and ultra high grade anthracite are harder than standard grade anthracite, and have a higher relative density. An example of a chemical formula for high-grade anthracite would be C<sub>240</sub>H<sub>90</sub>O<sub>4</sub>NS,<ref>{{cite web|title=Coal characteristics: Indiana Center for Coal Technology Research Basic Facts File #8|url=http://www.purdue.edu/discoverypark/energy/assets/pdfs/cctr/outreach/Basics8-CoalCharacteristics-Oct08.pdf|publisher=Indiana Center for Coal Technology Research|access-date=15 May 2012}}</ref> representing 94% carbon.<ref>{{cite web|url=http://www.webqc.org/molecular-weight-of-C240H90O4NS.html|title=Molar mass of C240H90O4NS|website=www.webqc.org}}</ref> UHG anthracite typically has a minimum carbon content of 95%.

They also differ in usage from standard grade anthracite (used mainly for power generation), being employed mainly in metallurgy as a cost-efficient substitute for [[coke (fuel)|coke]] in processes such as [[sintering]] and [[Pelletizing|pelletising]], as well as [[Pulverized coal injection method|pulverised coal injection]] (PCI) and direct injection into [[blast furnace]]s. They can also be used in [[water purification]] and domestically as a [[smokeless fuel]].

HG and UHG anthracite account for a small percentage of the total anthracite market. The major producing countries are Russia, Ukraine, Vietnam, South Africa and the US.

{| class="wikitable" style="clear:left"
|+Standard classifications by size
!Name     !!Imperial (inches) !!Metric (mm)
|-
|Chestnut || {{convert|7/8|-|1+1/2|in|mm|disp=table|abbr=on}}
|-
|Pea      || {{convert|9/16|-|7/8|in|mm|disp=table}}
|-
|Buckwheat|| {{convert|3/8|-|9/16|in|mm|disp=table}}
|-
|Rice     || {{convert|3/16|-|3/8|in|mm|disp=table}}
|-
|Barley   || {{convert|3/32|-|3/16|in|mm|disp=table}}
|}

The primary sizes used in the United States for domestic heating are Chestnut, Pea, Buckwheat and Rice, with Chestnut and Rice being the most popular. Chestnut and Pea are used in hand fired furnaces while the smaller Rice and Buckwheat are used in automatic stoker furnaces. Rice is currently the most sought-after size due to the ease of use and popularity of that type of furnace.

In [[South Wales]], a less elaborate classification is adopted, but great care is exercised in hand-picking and cleaning the coal from particles of pyrites in the higher qualities known as best malting coals, which are used for kiln-drying malt.{{sfn|Bauerman|1911|p=106}}<!-- Likely obsolete information -->

Anthracite dust can be made into [[coal briquette|briquettes]] and is sold in the United Kingdom under trade names such as [[Phurnacite]], Ancit and Taybrite.

===Semianthracite===
On the opposite end from high-grade anthracite coal, semianthracite coal is defined as a coal which is intermediate between anthracite coal and bituminous coal, and particularly a coal which approaches anthracite in nonvolatile character.<ref>{{cite web|url= https://www.merriam-webster.com/dictionary/semianthracite#:~:text=Definition%20of%20semianthracite,approaching%20anthracite%20in%20nonvolatile%20character |title=Definition of semianthracite|publisher=Merriam-Webster|accessdate=January 11, 2022}}</ref>

== Underground fires ==
{{See also|Coal-seam fire}}
[[File:Burning Culm Dump, Scranton, PA.jpg|thumb|A 1908 postcard of burning anthracite near [[Scranton, Pennsylvania]]]]
Historically, from time to time, underground seams of coal have caught fire, often from careless or unfortunate mining activities. The pocket of ignited coal is fed oxygen by vent paths that have not yet been discovered. These can smolder for years. Commonly, exhaust vents in populated areas are soon sensed and are sealed while vents in uninhabited areas remain undiscovered. Occasionally, vents are discovered via fumes sensed by passers-by, often in forested areas. Attempts to extinguish those remaining have at times been futile, and several such combustion areas exist today. The existence of an underground combustion site can sometimes be identified in the winter where fallen snow is seen to be melted by the warmth conducted from below. Proposals for harnessing this heat as geothermal energy have not been successful.

A vein of anthracite that caught fire in [[Centralia, Pennsylvania]], in 1962 has been burning ever since, turning the once-thriving borough into a [[ghost town]].<ref>Bellows, Alan (2006) [http://www.damninteresting.com/?p=479 "The Smoldering Ruins of Centralia"] DamnInteresting.com (accessed August 29, 2006)</ref>

== Major reserves ==
Geologically, the largest most concentrated anthracite deposit in the world is found in the [[Lackawanna Coal Mine]] in northeastern [[Pennsylvania]], United States in and around [[Scranton, Pennsylvania|Scranton]], Pennsylvania. Locally called the [[Coal Region]], the deposit contains {{convert|480|sqmi||||}} of coal-bearing rock which originally held 22.8 billion short tons (20.68 billion tonnes) of anthracite.<ref>{{Cite journal|last=Ashley|first=George H.|date=December 1945|title=Anthracite Reserves|url=https://scholarsphere.psu.edu/downloads/sn009w3579|journal=PAGS Progress Reports and Bulletins|number=130|access-date=2019-05-16|archive-date=2020-08-09|archive-url=https://web.archive.org/web/20200809002451/https://scholarsphere.psu.edu/downloads/sn009w3579|url-status=dead}}</ref> The geographic region is roughly 100 miles (161&nbsp;km) in length and 30 miles (48&nbsp;km) in width. Because of historical mining and development of the lands overlying the coal, it is estimated that 7 billion short tons (6.3 billion tonnes) of minable reserves remain. Other areas of the United States also contain several smaller deposits of anthracite, such as those historically mined in [[Crested Butte, Colorado]].

Among current producers, Russia, China, Poland, and Ukraine have the largest estimated recoverable reserves of anthracite. Other countries with substantial reserves include Vietnam and North Korea.<ref>{{cite web|url=http://www.marston.com/Portals/0/CoalTrans_Antra_Poland_2009.pdf|title=Marston – Anthracite production and exports: A world map}}</ref>

The Groundhog Anthracite Deposit in [[British Columbia]], Canada, is the world's largest previously undeveloped anthracite deposit. It is owned by the [[Australia]]n publicly-traded company Atrum Coal and has 1.57 billion tonnes of high grade anthracite.<ref>{{cite web|url=http://atrumcoal.com/projects/project-1/|title=Atrum Coal Groundhog Project – Atrum Coal|website=atrumcoal.com|access-date=2013-11-24|archive-date=2012-06-17|archive-url=https://web.archive.org/web/20120617155352/http://atrumcoal.com/projects/project-1/|url-status=dead}}</ref>

Anthracites of newer Tertiary or Cretaceous age are found in the [[Crowsnest Pass]] part of the [[Rocky Mountains]] in Canada and at various places in the [[Andes]] in Peru.{{sfn|Bauerman|1911|p=106}}

== See also ==
* {{annotated link|Antratsyt}}, named after a large supply of anthracite found there
* {{annotated link|Bituminous coal}}, a softer coal
* {{annotated link|History of coal miners}}
* {{annotated link|History of coal mining}}

== Explanatory notes ==
{{Reflist
| group = lower-alpha
}}

==References==
{{reflist}}
* {{cite EB9 |wstitle=Anthracite |volume=2 |page=106 |short=x |ref={{sfnref|''Encyclopædia Britannica''|1878}}}}

==Further reading==
* {{cite journal |last=Chandler |first=Alfred D. |title=Anthracite coal and the beginnings of the industrial revolution in the United States |journal=Business History Review |volume=46 |number=2 |year=1972 |pages=141–181|doi=10.2307/3113503 |jstor=3113503 |s2cid=154542035 }}
* {{cite book |author=Hudson Coal Company |title=The Story of Anthracite |location=New York |year=1932 |page=425}} – Useful overview of the industry in the 20th century; fair-minded with an operators perspective

===Primary sources===
* ''Report of the United states coal commission....'' (5 vol in 3; 1925) Official US government investigation. [http://babel.hathitrust.org/cgi/pt?id=coo.31924013933860;view=1up;seq=7 online vol 1-2]
** Tryon, Frederick Gale, and Joseph Henry Willits, eds. ''What the Coal Commission Found: An Authoritative Summary by the Staff'' (1925).
* General policies committee of anthracite operators. ''The anthracite coal strike of 1922: A statement of its causes and underlying purposes'' (1923); Official statement by the operators. [http://catalog.hathitrust.org/Record/001432268 online]

== External links ==
{{Commons category|Anthracite}}
{{AmCyc Poster|Anthracite}}
*{{cite EB1911|last=Bauerman|first=Hilary|author-link=Hilary Bauerman|wstitle=Anthracite|volume=2|pages=105–106}}
*[https://www.usgs.gov/faqs/what-are-types-coal "What are the types of coal?"] at [[United States Geological Survey|U.S. Geological Survey]] 
*[http://www.anthracitemuseum.org/ Pennsylvania Anthracite Museum] in [[Scranton, Pennsylvania]]

{{Coal}}
{{Rock type}}
{{Authority control}}

[[Category:Coal]]
[[Category:Coal mining]]
[[Category:Metamorphic rocks]]
[[Category:Organic minerals]]