Natron



Natron is a naturally occurring mixture of mineralogy the term natron often means only the prevailing hydrated sodium carbonate found in the historical salt.

Etymology

The English word natron is a French cognate derived from the Spanish natrón through the Arabic natrun from Greek nitron which derived from the Ancient Egyptian word netjeri, stemming from Wadi El Natrun, Egypt. The modern chemical symbol for sodium, Na, is an abbreviation of that element's new Latin name natrium, which was derived from natron.

Importance in antiquity

Historical natron was harvested directly as a salt mixture from dry lake beds in ancient Egypt and has been used for thousands of years as a cleaning product for both the home and body. Blended with oil, it was an early form of antiseptics for wounds and minor cuts. Natron can be used to dry and preserve fish and meat. It was also an ancient household insecticide.

The mineral was used in Egyptian mummification because it absorbs water and behaves as a drying agent. Moreover, when exposed to moisture the bicarbonate in natron increases pH, which creates a hostile environment for bacteria. Culturally, natron was generally thought to enhance spiritual safety for both the living and the dead. Natron was added to castor oil to make a smokeless fuel which allowed Egyptian artisans to paint elaborate artworks inside ancient tombs without staining them with soot.

Natron is an ingredient for the making of a distinct color called Egyptian blue. It was used along with sand in ceramic and glass making by the Romans and others at least until 640 CE. The mineral was also employed as a flux to solder precious metals together.

Declining use

Most of natron's uses both in the home and by industry were gradually replaced with often closely related sodium compounds and minerals. Natron's soda ash (the mixture's chief compound ingredient) and other chemicals. Soda ash also replaced natron in glassmaking. Many of its ancient household roles are now filled by ordinary baking soda, natron's secondary ingredient.

Chemistry of hydrated sodium carbonate

The compound sodium carbonate decahydrate (Na2CO3·10 H2O) found in historical natron has a specific gravity of 1.42 to 1.47 and a thermonatrite Na2(CO3)·(H2O).

Source of soda ash

Hydrated sodium carbonate is stable at room temperature but recrystallizes at only 32°C to sodium carbonate heptahydrate, Na2CO3·7H2O, then above 37-38°C to sodium carbonate monohydrate, Na2(CO3)·(H2O). This recrystallization from decahydrate to monohydrate releases much crystal water in a mostly clear, colorless salt solution with little solid trona.

Geological occurrence

(List may include sources of either natron or hydrated sodium carbonate)

  • Quebec, Canada
    • Rouville County
    • Mont-Saint-Hilaire
  • Interior British Columbia, Canada
  • Wadi El Natrun, Egypt
  • Showa Province, Ethiopia
  • Hungary
    • Bács-Kiskun County, (Great Hungarian Plain)
    • Szabolcs-Szatmár-Bereg County (Great Hungarian Plain)
  • Campania, Italy
    • Province of Naples
    • Somma-Vesuvius Complex
  • Russia (Northern Region)
    • Murmanskaja Oblast
    • Kola Peninsula
    • Khibiny Massif
    • Lovozero Massif
    • Alluaiv Mountain
    • Umbozero Mine
    • Kedykverpakhk Mountain
  • England, UK
    • Cornwall
    • St Just District
    • Botallack - Pendeen Area
    • Botallack, and Botallack Mine
  • California, USA
    • Inyo County
  • Nevada, USA
    • Churchill County (Soda Lake District)
    • Humboldt County
    • Mineral County
  • Oregon, USA
    • Lake County
  • Washington, USA
    • Okanogan County

See also

Saltpeter

 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Natron". A list of authors is available in Wikipedia.