Salt

Description
"Nay, my men are sick to stretch their legs ashore, and nigh to scurvy from chewing salt pork."

- The Black Stranger

Civilization pivots around salt, communities forming, like growths, around sources of the stuff. Salt is mined, and it is boiled from salt-laden water. It flavors food. Sometimes, it serves as a form of currency. Perhaps most importantly, salt is the best known food preserver, especially for meat.