salt, common

A rock salt mine. Salt occurs naturally in underground deposits and occasionally in surface deposits, as the mineral halite (commonly known as rock salt). Salt domes such as this are produced by tectonic forces. Both bedded salt deposits and salt domes (also called diapirs) are mined by drilling and blasting.

White crystalline solid, found dissolved in seawater and as rock salt (the mineral halite) in large deposits and salt domes. Common salt is used extensively in the food industry as a preservative and for flavouring, and in the chemical industry in the making of chlorine and sodium.

While common salt is an essential part of our diet, some medical experts believe that excess salt can lead to high blood pressure and increased risk of heart attacks and strokes. A high level of salt in the diet presents the greatest risk to those who are overweight, according to a 1999 US study. Salt has historically been considered a sustaining substance, often taking on religious significance in ancient cultures. Roman soldiers were paid part of their wages as salt allowance (Latin salerium argentinium), hence the term ‘salary’.