Question: Where is most of the compound used in the topical application of magnesium found in North America?

Context paragraphs:
Jagua Tattoo: Jagua Tattoo is a temporary form of skin decoration resulting from the application of an extract of the fruit "Genipa americana", also known as "Jagua".  This fruit has been used for body ornamentation and medicinal purposes in many areas of South America for centuries.  It has only recently been introduced in North America and Europe as an addition to henna body art, also called Mehendi, Mehandi, or Mehndi in India.  (The term henna tattoo is often used as a generic term for temporary tattoos.)

Ammonium nitrate: Ammonium nitrate is a chemical compound, the nitrate salt of the ammonium cation.  It has the chemical formula NHNO, simplified to NHO.  It is a white crystal solid and is highly soluble in water.  It is predominantly used in agriculture as a high-nitrogen fertilizer.  Its other major use is as a component of explosive mixtures used in mining, quarrying, and civil construction.  It is the major constituent of ANFO, a popular industrial explosive which accounts for 80% of explosives used in North America; similar formulations have been used in improvised explosive devices.  Many countries are phasing out its use in consumer applications due to concerns over its potential for misuse.

Magnesium chloride: Magnesium chloride is the name for the chemical compound with the formula MgCl and its various hydrates MgCl(HO).  These salts are typical ionic halides, being highly soluble in water.  The hydrated magnesium chloride can be extracted from brine or sea water.  In North America, magnesium chloride is produced primarily from Great Salt Lake brine.  It is extracted in a similar process from the Dead Sea in the Jordan valley.  Magnesium chloride, as the natural mineral bischofite, is also extracted (via solution mining) out of ancient seabeds; for example, the Zechstein seabed in northwest Europe.  Some magnesium chloride is made from solar evaporation of seawater.  Anhydrous magnesium chloride is the principal precursor to magnesium metal, which is produced on a large scale.  Hydrated magnesium chloride is the form most readily available.

Magnesium oil: Magnesium oil (also referred to as transdermal magnesium) is a mixture of Magnesium chloride in water.  In reality it is not an oil.  It is applied to the skin.  The magnesium is absorbed through the skin and is claimed to have health benefits, such as for the treatment of magnesium deficiency, to relieve muscle pains and aches (especially headaches), and enhance to relaxation.

Humulus japonicus: Humulus japonicus, known as wild hop or Japanese hop, synonym "H. scandens" is an ornamental plant in the Cannabaceae family.  Originally found in temperate parts of Asia (China, Japan, Korea, Taiwan and Russia) and the tropical environment of Vietnam, "Humulus japonicus" was imported to the North America in the 1800s for use in an Asian tonic and as an ornamental plant.  Since its arrival in North America, Japanese hop has been very successful in spreading in North America.  It has a wide distribution and can be found throughout the Northeastern U.S. and eastern Canada.  It is considered an invasive species in North America.  The composition and chemistry of the oils found in "Humulus japonicus" differs from its relative the common hop, "Humulus lupulus."  As a result, the Japanese hop is not used in the production of beer.

Paraveterinary workers in France: Veterinary support personnel in France are organized according to "La Convention Collective Nationale des Cabinets et Cliniques Vétérinaires", a state sponsored trade union organized by French veterinarians, and consist of five pay echelons.  Echelon 1 consists of housekeeping and maintenance personnel, echelon 2 consists of reception and secretarial personnel, while echelons 3-5 are "Auxiliaires Vétérinaires" directly responsible for animal care.  Those working at echelons 4 and 5 have undergone formal apprenticeships, administered by "le Groupement d'Intérét Public Formation Santé Animale et Auxiliaire vétérinaire" (GIPSA),of one and two years respectively and are titled "Auxiliaires Vétérinaires Quatre" (AVQ or AV4) and "Auxiliaire Spécialisé Vétérinaire" (ASV).  The former's job description is similar to that of the approved veterinary assistant in North America while the latter's job description is similar to veterinary technicians in North America.  The title of "Technicien en Santé Animale" (TSA) is also used in France but is awarded after a college level course of study in animal health and is not a replacement for the officially recognized titles of AVQ and ASV.  Those in possession of a combination of the titles TSA and ASV are the equivalents of veterinary technologists in North America and can often be found working in production animal medicine, pharmacological research, or at veterinary school teaching hospitals.  At present there is not an official national association representing the interests of veterinary auxiliaries.

Amanita regalis: Amanita regalis, commonly known as the royal fly agaric or the king of Sweden Amanita, is a species of fungus in the Amanitaceae family.  Common in Scandinavian countries, it is also found in eastern and northern Europe.  In North America, its distribution is restricted to Alaska.  The fruit bodies of the fungus somewhat resemble the fly agaric ("Amanita muscaria"), and it was formerly regarded as a variety of this species.  "A. regalis" differs from it in being larger, with a liver-brown cap bearing numerous scabs, and in having a stem which is yellow-ochre at the base, with patches or rings of patches.  Chemical analysis has shown that this species contains muscimol, the same psychoactive compound found in "A. muscaria".

Psilocybe yungensis: Psilocybe yungensis is a species of psychedelic mushroom in the Strophariaceae family.  In North America, it is found in northeast, central and southeastern Mexico.  In South America, it has been recorded from Bolivia, Colombia, and Ecuador.  It is also known from the Caribbean island Martinique, and China.  The mushroom grows in clusters or groups on rotting wood.  The fruit bodies have conical to bell-shaped reddish- to orangish-brown caps that are up to 2.5 cm in diameter, set atop slender stems 3 to long.  The mushrooms stain blue when bruised, indicative of the presence of the compound psilocybin.  "Psilocybe yungensis" is used by Mazatec Indians in the Mexican State of Oaxaca for entheogenic purposes.

Mesquite flour: Mesquite flour is made from the dried and ground pods of the mesquite ("Prosopis" spp.) .  The tree grows throughout North America in arid climates.  The flour made from the long, beige-colored seed pods has a sweet, slightly nutty flavor and can be used in a wide variety of applications.  It has a high-protein, low-glycemic content and can serve as a gluten-free replacement for flours.  In the past, Indigenous American Indians relied on these mesquite pods as an important food source.  The bean pods of the mesquite tree are dried and ground into a flour ("pinole").  This flour is rich in dietary fiber (25%) and protein (13%).  It also contains significant quantities of calcium, magnesium, potassium, iron, zinc, and the amino acid lysine, and it is low in fat (around 3%).

Alpha-Pinene: α-Pinene is an organic compound of the terpene class, one of two isomers of pinene.  It is an alkene and it contains a reactive four-membered ring.  It is found in the oils of many species of many coniferous trees, notably the pine.  It is also found in the essential oil of rosemary ("Rosmarinus officinalis") and "Satureja" "myrtifolia" (also known as "Zoufa" in some regions.)  Both enantiomers are known in nature; (1"S",5"S")- or (−)-α-pinene is more common in European pines, whereas the (1"R",5"R")- or (+)-α-isomer is more common in North America.  The racemic mixture is present in some oils such as eucalyptus oil and orange peel oil.

Supporting paragraphs: Magnesium oil Magnesium chloride
Answer: Great Salt Lake brine