Niter or
nitre (
BrE- Computing :*Barren Realms Elite, a multi-player bulletin board system strategy game*Basic regular expression, expressions used for computerized text matching*Business rules engine, a software system to manage and execute business rules- Organisations :...
) is the mineral form of
potassium nitratePotassium nitrate is a chemical compound with the formula KNO3. It is an ionic salt of potassium ions K+ and nitrate ions NO3−.It occurs as a mineral niter and is a natural solid source of nitrogen. Its common names include saltpetre , from medieval Latin sal petræ: "stone salt" or possibly "Salt...
, KNO
3, also known as
saltpeter (AmE) or
saltpetre (BrE). Historically, the term "niter" –
cognateIn linguistics, cognates are words that have a common etymological origin. This learned term derives from the Latin cognatus . Cognates within the same language are called doublets. Strictly speaking, loanwords from another language are usually not meant by the term, e.g...
with "natrium", a Latin word for
sodiumSodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal and is a member of the alkali metals; its only stable isotope is 23Na. It is an abundant element that exists in numerous minerals, most commonly as sodium chloride...
– has been very vaguely defined, and it has been applied to a variety of other minerals and chemical compounds, including
sodium nitrateSodium nitrate is the chemical compound with the formula NaNO3. This salt, also known as Chile saltpeter or Peru saltpeter to distinguish it from ordinary saltpeter, potassium nitrate, is a white solid which is very soluble in water...
(also "soda niter", "cubic niter", or nitratite),
sodium carbonateSodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...
and
potassium carbonatePotassium carbonate is a white salt, soluble in water , which forms a strongly alkaline solution. It can be made as the product of potassium hydroxide's absorbent reaction with carbon dioxide. It is deliquescent, often appearing a damp or wet solid...
.
Because of its ready solubility in water, niter is most often found in arid environments. A major source of sodium (not potassium) nitrate mineral is the
Atacama desertThe Atacama Desert is a plateau in South America, covering a strip of land on the Pacific coast, west of the Andes mountains. It is, according to NASA, National Geographic and many other publications, the driest desert in the world...
in Chile. Potassium and other nitrates are of great importance for use in fertilizers, and, historically, gunpowder. Much of the world's demand is now met by synthetically produced nitrates, though the natural mineral is still mined and is still of significant commercial value.
Description
Niter is a colorless to white mineral crystallizing in the orthorhombic
crystal systemIn crystallography, the terms crystal system, crystal family, and lattice system each refer to one of several classes of space groups, lattices, point groups, or crystals...
. It usually is found as massive encrustations and effervescent growths on
caveA cave or cavern is a natural underground space large enough for a human to enter. The term applies to natural cavities some part of which is in total darkness. The word cave also includes smaller spaces like rock shelters, sea caves, and grottos.Speleology is the science of exploration and study...
rn 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
twinningCrystal twinning occurs when two separate crystals share some of the same crystal lattice points in a symmetrical manner. The result is an intergrowth of two separate crystals in a variety of specific configurations. A twin boundary or composition surface separates the two crystals....
.
History
Niter as a term has been known since ancient times, although there is much historical confusion with
natronNatron is a naturally occurring mixture of sodium carbonate decahydrate and about 17% sodium bicarbonate along with small quantities of household salt and sodium sulfate. Natron is white to colourless when pure, varying to gray or yellow with impurities...
(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 Greek
νιτρων nitron from Ancient Egyptian
netjeri, related to the Hebrew
néter, for salt-derived ashes (their interrelationship is not clear).
The Hebrew
néter may have been used as, or in conjunction with soap, as implied by
JeremiahJeremiah Hebrew：יִרְמְיָה , Modern Hebrew:Yirməyāhū, IPA: jirməˈjaːhu, Tiberian:Yirmĭyahu, Greek:Ἰερεμίας), meaning "Yahweh exalts", or called the "Weeping prophet" was one of the main prophets of the Hebrew Bible...
2:22, "For though thou wash me with nitre, and take thee much sope…" However, it is not certain which substance (or substances) the Biblical "neter" refers to, with some suggesting
sodium carbonateSodium carbonate , Na2CO3 is a sodium salt of carbonic acid. It most commonly occurs as a crystalline heptahydrate, which readily effloresces to form a white powder, the monohydrate. Sodium carbonate is domestically well-known for its everyday use as a water softener. It can be extracted from the...
. Indeed, the Neo Latin word for sodium natrium is derived from this same class of desert minerals called
natron (French) from Spanish
natrón through Greek
νιτρων (
nitron), derived from Ancient Egyptian
netjeri, referring to the carbonate sodium salts occurring in the deserts of Egypt, not the
nitrated sodium saltsNitratine or nitratite, also known as cubic niter , soda niter or Chile saltpeter , is a mineral, the naturally occurring form of sodium nitrate, NaNO3. Nitratine crystallizes in the trigonal system, but rarely occurs as well formed crystals. It is isostructural with calcite...
typically occurring in the deserts of
ChileChile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
(classically known as "Chilean
saltpeterSaltpeter or saltpetre often refers to:*Potassium nitrate, or the mineral niter, the critical oxidizing component of gunpowder, and a food preservative.It may also refer to:...
" and variants of this term).
A term (ἀφρόνιτρον) 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.
Niter was used to refer specifically to nitrated salts known as various types of
saltpeterSaltpeter or saltpetre often refers to:*Potassium nitrate, or the mineral niter, the critical oxidizing component of gunpowder, and a food preservative.It may also refer to:...
(only nitrated salts were good for making gunpowder) by the time niter and its derivative nitric acid were first used to name the element
nitrogenNitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
, in 1790.
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