or tequexquite (from Nahuatl tequixquitl) tetl: stone, and quix-quitl: sprout, sprouting stone. Quixquitl has also been said to translate as “foaming/efflorescent” (1) (Parsons 2001) or “something that comes out by itself, that floats” (algo que sale por sí mismo, que flota).

1. In chemistry, efflorescence (which means “to flower out” in French) is the migration of a salt to the surface of a porous material, where it forms a coating.

Also called : sal de tierra (land/earth salt), sal de laguna (lagoon salt)

Tequesquite is a natural mineral salt containing compounds of sodium chlorate, sodium carbonate, and sodium sulphate, used in Mexico since pre-Hispanic times mainly as a food seasoning. It is found naturally in central Mexico particularly in previously lacustrine (1) environments where the mineral salt forms a sedimentary crust.

1. relating to or associated with lakes, which is relevant as much of the Basin of Mexico was covered by lakes.

Its appearance is similar to that of common table salt in coarseness, but with a more greyish colour.

The shield of the municipality of Tequixquiac in the northern part of the State of México (1) is constituted by the stylized glyph that represents the cross-section of an apantli (2); in the centre of the image sits an amorphous crystallization representative of tequesquite; at the top, crowned by two undulations, representing atl (3), which are adorned with a pearl and a snail.

1. about 65km from the centre of México City
2. canal or irrigation ditch
3. water; a body of water, such as a lake, river, or ocean; floods, flooding, liquid beverage, even chocolate; urine; fontanelle; also, a calendrical marker

1. a place name, especially one derived from a topographical (2) feature.
2. relating to the arrangement or accurate representation of the physical features of an area.

Tequesquite is classified in five categories with the following local denominations: confitillo, cascarilla, espumillo, polvillo, and dark tequesquite, depending on the collecting season and place of origin (Flores, 1918)(1)

1. At the “2nd International Congress on the Anthropology of Salt” held in Los Cabos Mexico 2017, the following varieties were mentioned : gravel “confitillo”, husk “cascarilla” or “tepalcatillo”, mousse “espumilla”, dust “polvillo” or crystalline “cristalino” and black-coloured tequesquite “tequesquite prieto”.

Today only 4 varieties are commonly listed (some authors list only 3 varieties) (Castellon Huerta 2007)

1. Espumilla (espumillo)
2. Confitillo
3. Cascarilla
4. Polvillo

Espumillo and confitillo are considered as superior in quality. They are formed from the water which is retained in small ponds when the water level of the Texcoco lake drops. Cascarilla and Polvillo are less appreciated and are collected from spontaneously produced efflorescence on the ground.

CHEMICAL COMPOSITION:
Confitillo:
• Soda carbonate: 28%
• Sodium chloride: 30%
• Insoluble clay: 35%
• Moisture 7%

Cascarilla:
• Sodium chloride: 46%
• Soda carbonate: 20%
• Sodium sulfate: 4%
• Insoluble clays, and moisture 30%

Polvillo:
• Fine clay earth, insoluble: 85%
• Sodium chloride: 6%
• Sodium sulfate: 1.5%
• Sodium carbonate: 0.5%
• Moisture: 7.0%

Some locations in Mexico where it is mined are Lake Texcoco (previously the largest saline lake in México), Tequixquiac and Tequexquinahuac in the state of Mexico, Laguna Tequesquitengo in the state of Morelos, Nopalucan and Tequexquitla, in the state of Tlaxcala , Tequisquiapan, in the state of Querétaro, Tequesquite, in the state of Jalisco, Totolcingo lagoon in the state of Puebla and La Salada, in the state of Zacatecas.

Tequesquite has many uses as an ingredient in traditional Mexican dishes. Mainly used in products made from corn, such as tamales, to accentuate their flavour (and in the case of tamales as a leavening agent which gives the tamal a “spongey” texture). It is also used for cooking nopales and other vegetables (as it helps retains their bright green colour), to soften dried beans or as a meat tenderizer, in a manner similar to how you might use sodium bicarbonate.

To use it as a leavening agent; boil a solid tequesquite stone and the shells of ten tomatillos in a cup of water. Once the stone has been dissolved and the water has boiled remove from heat and let stand. When it is cold it is strained and added to the masa. Another recipe indicates the same procedure, but using 15 grams of tequesquite, 15 tomatillo shells and 1/4 L (250ml = 1 cup) water.

Mesoamericans used it in the cooking water when preparing Itzmiquilitl (1). This was said to improve the digestibility of this plant.

1. Portulaca oleraceae = purslane = verdolagas : itzmītl “obsidian arrow” +‎ quilitl “vegetable”. See Post Quelite : Verdolagas : Purslane

Medicinal use

In la Sierra Norte de Puebla a pedazo (piece) of tequesquite is added to an infusion of Piper sancti-felicis (a relative of Hoja Santa – Piper auritum) to treat empacho. From an allopathic point of view this does make sense. One of the primary constituents of (the higher quality) tequesquites is sodium bicarbonate. Sodium bicarbonate (commonly known as baking soda) is perhaps the best-known of the sodium-containing antacids (1). It is potent and fast-acting. As its name suggests, it is high in sodium. If you’re on a salt-restricted diet, and especially if the diet is intended to treat high blood pressure (hypertension) over using these antacids can be potentially dangerous by exacerbating high blood pressure.

1. Alka-Seltzer is probably the best known incarnation of a sodium bicarbonate antacid

Treatment with sodium bicarbonate in patients with chronic kidney disease potentially slows progression in renal
insufficiency and can avoid or reduce the need for kidney dialysis. It has also shown that it has positive outcomes for patients receiving dialysis by having positive effects on appetite and nutritional status (de Brito-Ashurst 2009)

Sodium bicarbonate is often given to reduce the pH level of urine (making it more alkaline = less acidic) in cases of infection that causes dysuria (1).

1. painful urination

• Blas Román Castellón Huerta : (2007) : Un grano de sal: aportaciones etnoarqueológicas al estudio histórico de una industria ancestral (A grain of salt: ethnoarchaeological contributions to the historical study of an ancestral industry) : Vol I : Anales del Instituto de Biologia Serie Zoologia : Universidad Nacional Autónoma de México
• Ione de Brito-Ashurst, Mira Varagunam, Martin J. Raftery and Muhammad M. Yaqoob : Bicarbonate Supplementation Slows Progression of CKD and Improves Nutritional Status : JASN September 2009, 20 (9) 2075-2084; DOI: https://doi.org/10.1681/ASN.2008111205
• Flores, T. (1918). El tequesquite del Lago de Texcoco. Anales del Instituto Geológico de México
• Hernández, Dante & Martínez-Jerónimo, Fernando. (2016). Detailed chemical composition of tequesquite, a pre-Hispanic and traditional mineral resource used in Mexico for culinary purposes. Acta Universitaria. 26. 31-39. 10.15174/au.2016.987.
• Miguel Ángel Martínez Alfaro, Virginia Evangelista Oliva, Myrna Mendoza Cruz, Gustavo Morales García, Guadalupe Toledo Olazcoaga y Alfredo Wong León. : (1995) CATÁLOGO DE PLANTAS ÚTILES DE LA SIERRA NORTE DE PUEBLA, MÉXICO : UNIVERSIDAD NACIONAL AUTÓNOMA DE MÉXICO
• Ramón Ojeda-Mestre, Ashley Dumas, Roxana-Gabriela Curcă (Editors) : Second International Congress on the Anthropology of Salt. 12–16 October 2017, Los Cabos, Mexico.
• Parsons, J. (2001). The Last Saltmakers of Nexquipayac, Mexico: An Archaeological Ethnography. Ann Arbor, Michigan: University of Michigan Press. doi:10.3998/mpub.11395003
• Ramos, S. & Garibay-Chávez, Guadalupe & Curiel, Arturo. (2018). Identification, collection and consumption of weeds and wild vegetables in Mexican communities: institutionalized local ancestral indigenous knowledge as ecological literacy, place and identity. Cultural Studies of Science Education. 10.1007/s11422-017-9852-y.