It is a product of the Solvay process used to produce sodium carbonate:[3] Not only is that method the principal one for the manufacture of ammonium chloride, but also it is used to minimize ammonia release in some industrial operations.

[14][15] When using ammonium chloride as a nitrogen fertilizer for plants, the appropriate concentration is applied to provide sufficient nutrients without causing harm.

[22] In agricultural applications the solution is used shortly after preparation,[23] for the following reasons: Ammonium chloride was used in pyrotechnics in the 18th century but was superseded by safer and less hygroscopic chemicals.

Its purpose was to provide a chlorine donor to enhance the green and blue colours from copper ions in the flame.

[citation needed] Ammonium chloride, under the name sal ammoniac or salmiak is used as food additive under the E number E510, working as a yeast nutrient in breadmaking and as an acidifier.

Ammonium chloride is used to spice up dark sweets called salty liquorice (popular in the Nordic countries, Benelux and northern Germany),[32] in baking to give cookies a very crisp texture, and in the liquor Salmiakki Koskenkorva for flavouring.

In Turkey, Iran, Tajikistan, India, Pakistan and Arab countries it is called "noshader" and is used to improve the crispness of snacks such as samosas and jalebi.

[34] In paleontology, ammonium chloride vapor is deposited on fossils, where the substance forms a brilliant white, easily removed and fairly harmless and inert layer of tiny crystals that covers up any coloration the fossil may have, and if lighted at an angle highly enhances contrast in photographic documentation of three-dimensional specimens.

Around the turn of the 20th century, ammonium chloride was used in aqueous solution as the electrolyte in Leclanché cells that found a commercial use as the "local battery" in subscribers' telephone installations.

The incorporation of ammonium chloride in the albumen solution was a significant factor in the quality and popularity of this photographic process.

[41] The process involves mixing egg whites (albumen) with ammonium chloride to create a viscous solution.

[45] Pliny, in Book XXXI of his Natural History, refers to a salt produced in the Roman province of Cyrenaica named hammoniacum, so called because of its proximity to the nearby Temple of Jupiter Amun (Greek Ἄμμων Ammon).

According to Herbert Hoover's commentary in his English translation of Georgius Agricola's De re metallica, it is likely to have been common sea salt.

[49] At that time, ammonium chloride came from two sources: (1) the vents of underground coal fires in Central Asia, specifically, in the Tian Shan mountains (which extend from Xinjiang province of northwestern China through Kyrgyzstan) as well as in the Alay (or Alai) mountains of southwestern Kyrgyzstan, and (2) the fumaroles of the volcano Mount Taftan in southeastern Iran.

)[53] Ammonium chloride was then transported along the Silk Road eastwards to China and westwards to the Muslim lands and Europe.

Around 800 A.D. the Iranian chemist Jabir ibn Hayyan discovered ammonium chloride in the soot that resulted from burning camel dung, and this source became an alternative to those in Central Asia.

This included both naturally occurring sal ammoniac and synthetic ammonium chloride produced from organic substances.