niter

Niter is a colorless to white mineral crystallizing in the orthorhombic crystal system. It is the mineral form of potassium nitrate, {{chem2|KNO3}}, and is soft (Mohs hardness 2), highly soluble in water,{{cite book |editor1-last=Jackson |editor1-first=Julia A. |title=Glossary of geology. |date=1997 |publisher=American Geological Institute |location=Alexandria, Virginia |isbn=0922152349 |edition=Fourth |chapter=niter}} and easily fusible. Its crystal structure resembles that of aragonite, with potassium replacing calcium and nitrate replacing carbonate.{{cite book |last1=Klein |first1=Cornelis |last2=Hurlbut |first2=Cornelius S. Jr. |title=Manual of mineralogy : (after James D. Dana) |date=1993 |publisher=Wiley |location=New York |isbn=047157452X |edition=21st |page=418}} It occurs in the soils of arid regions and as massive encrustations and efflorescent growths on cavern walls and ceilings where solutions containing alkali potassium and nitrate seep into the openings. It occasionally occurs as prismatic acicular crystal groups, and individual crystals commonly show pseudohexagonal twinning on [110]. Niter and other nitrates can also form in association with deposits of guano and similar organic materials.{{cite web |last1=Anthony |first1=John W. |last2=Bideaux |first2=Richard A. |last3=Bladh |first3=Kenneth W. |last4=Nichols |first4=Monte C. |title=Niter |url=http://www.handbookofmineralogy.org/pdfs/niter.pdf |website=Handbook of Mineralogy |publisher=Mineral Data Publishing |access-date=28 December 2021 |date=2005}}

Niter as a term has been known since ancient times, although there is much historical confusion with natron (an impure sodium carbonate/bicarbonate), and not all of the ancient salts known by this name or similar names in the ancient world contained nitrate. The name is from the Ancient Greek {{lang|grc|νιτρων}} {{lang|grc-Latn|nitron}} from Ancient Egyptian {{lang|egy-Latn|netjeri}}, related to the Hebrew {{lang|he-Latn|néter}}, for salt-derived ashes (their interrelationship is not clear).{{oed|nitre}}

The Hebrew {{lang|he-Latn|néter}} may have been used as, or in conjunction, with soap, as implied by Jeremiah 2:22, "For though thou wash thee with niter, and take thee much soap..." However, it is not certain which substance (or substances) the Biblical "neter" refers to, with some suggesting sodium carbonate.{{cite journal |last1=Haberfield |first1=Paul |title=What's in a name: NaNO3 |journal=Journal of Chemical Education |date=January 1985 |volume=62 |issue=1 |pages=56 |doi=10.1021/ed062p56|bibcode=1985JChEd..62...56H }}

The Neo-Latin word for sodium, {{lang|la|natrium}}, is derived from this same class of desert minerals called {{lang|fr|natron}} (French){{oed|natrium}} through Spanish {{lang|es|natrón}} from Greek {{lang|grc|νίτρον}} ({{lang|grc-Latn|nitron}}), derived from Ancient Egyptian {{lang|egy-Latn|netjeri}}, referring to the sodium carbonate salts occurring in the deserts of Egypt, not the nitratine (nitrated sodium salts) typically occurring in the deserts of Chile (classically known as "Chilean saltpeter" and variants of this term).{{Cite web |url=http://www.balashon.com/2008/07/neter-and-nitrogen.html |title=neter and nitrogen |last1=Curwin |first1=David |year=2008}}{{self-published inline|date=December 2021}}

A term ({{lang|grc|ἀφρόνιτρον}}, {{lang|grc-Latn|aphronitron}} or aphronitre) which translates as "foam of niter" was a regular purchase in a fourth-century AD series of financial accounts, and since it was expressed as being "for the baths" was probably used as soap.More conventional soap also appears in the accounts but was more expensive: John Matthews, The Journey of Theophanes, Yale UP 2006

Niter was used to refer specifically to nitrated salts known as various types of saltpeter (only nitrated salts were good for making gunpowder) by the time niter and its derivative nitric acid were first used to name the element nitrogen, in 1790.{{oed|nitrogen}}

{{See also|Potassium nitrate#Historical production}}

Because of its ready solubility in water, niter is most often found in arid environments and often in conjunction with other soluble minerals like halides, iodates, borates, gypsum, and rarer carbonates and sulphates.{{cite book |last1=Reeves |first1=C. C. |chapter=Economic Significance of Playa Lake Deposits |title=Modern and Ancient Lake Sediments |date=24 November 1978 |pages=279–290 |doi=10.1002/9781444303698.ch15|isbn=9780632002344 }}{{cite journal |last1=Ericksen |first1=G.E. |year=1983 |title=The Chilean Nitrate Deposits: The origin of the Chilean nitrate deposits, which contain a unique group of saline minerals, has provoked lively discussion for more than 100 years |journal=American Scientist |volume=71 |number=4 |pages=366–374 |jstor=27852136}}

Niter occurs naturally in certain places like the "Caves of Salnitre" (Collbató) known since the Neolithic. In the "Cova del Rat Penat", guano (bat excrements) deposited over thousands of years became saltpeter after being leached by the action of rainwater.{{citation needed|date=January 2022}}

In 1783, Giuseppe Maria Giovene and Alberto Fortis together discovered a "natural nitrary" in a doline close to Molfetta, Italy, named Pulo di Molfetta. The two scientists discovered that niter formed inside the walls of the caves of the doline, under certain conditions of humidity and temperature.{{cite journal |title=Necrologia – Giuseppe Maria Giovene – Arciprete della Cattedrale Chiesa di Molfetta |author=Pietro Filioli |journal=Annali Civili del Regno delle Due Sicilie |year=1837 |volume=25, gennaio e febbraio |publisher=Tipografia del Real Ministero degli Affari Interni nel Reale Albergo de' Poveri |url=https://books.google.com/books?id=CC1FAAAAYAAJ&pg=PA35 |page=39|language=it}} After the discovery, it was suggested that manure could be used for agriculture, in order to increase the production, rather than to make gunpowder.{{Cite web |url=https://books.google.com/books?id=hr3g4qMtHfsC&pg=PA301 |title = Opuscoli scelti sulle scienze e sulle arti tratti dagli Atti delle Accademie, e dalle altre Collezioni filosofiche, e letterarie, e dalle opere più recenti inglesi, tedesche, francesi, latine, e italiane, e da manoscritti originali, e inediti: 12 |year=1789 |language=it}} The discovery was challenged by scholars until chemist Giuseppe Vairo and his pupil Antonio Pitaro confirmed the discovery. Naturalists sent by academies from all Europe came in large number to visit the site; since niter is a fundamental ingredient in the production of gunpowder, these deposits were of considerable strategic interest.{{cite journal |title=Elogio storico del canonico arciprete Giuseppe Maria Giovene |author=Andrea Tripaldi |journal=Memorie di Matematica e di Fisica della Società Italiana delle Scienze Residente in Modena |year=1841 |publisher= Tipi della R. D. Camera |location=Modena |volume=22 |url=https://books.google.com/books?id=0mmRYNPjNBAC&pg=PR1 |language=it }}{{rp|8–10}} The government started extraction. Shortly thereafter, Giovene discovered niter in other caves of Apulia.{{rp|9–10}}{{cite book |title=Lettera del Sig. canonico D. Giuseppe Maria Giovene, Vicario generale di Molfetta, al Sig. Abate Alberto Fortis, contenente varie osservazioni sulla nitrosità naturale della Puglia |author=Giuseppe Maria Giovene |date=7 August 1784 |location=Molfetta |url=https://books.google.com/books?id=hr3g4qMtHfsC&pg=PA309 |language=it}} The remnants of the extraction plant is a site of industrial archaeology, although currently not open to tourists.{{Cite web |url=https://www.molfettafree.it/content_/zoom.asp?id_news=7117|title=PER VEDERE IL PULO DI MOLFETTA ACCONTENTATEVI DI ARRAMPICARVI! |website=molfettafree.it}}{{Dead link |date=August 2023 |bot=InternetArchiveBot |fix-attempted=yes }}

Related minerals are soda niter (sodium nitrate), ammonia niter or gwihabaite (ammonium nitrate), nitrostrontianite (strontium nitrate), nitrocalcite (calcium nitrate), nitromagnesite (magnesium nitrate), nitrobarite (barium nitrate) and two copper nitrates, gerhardtite and buttgenbachite; in fact all of the natural elements in the first three columns of the periodic table and numerous other cations form nitrates which are uncommonly found for the reasons given, but have been described. Niter was used to refer specifically to nitrated salts known as various types of saltpeter (only nitrated salts were good for making gunpowder) by the time niter and its derivative nitric acid were first used to name the element nitrogen, in 1790.{{citation needed|date=January 2022}}

• {{Annotated link|Caliche}}
• Nitratine - Sodium based fertilizer

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• [http://www.balashon.com/2008/07/neter-and-nitrogen.html Etymology of "niter"]
• [https://web.archive.org/web/19970430135256/http://xroads.virginia.edu/~HYPER/POE/cask.html Poe's The Cask of Amontillado]

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Category:Nitrate minerals

Category:Potassium minerals

Category:Orthorhombic minerals

Category:Minerals in space group 36

Category:Potash

Category:History of mining

Category:Nitrogen