Coarse-grain salt by John Spottiswood.

Most recipes calling for salt intend for you to use finely ground salt, though coarse salt is better for certain things, like making beds for oysters and salt crusts on meat or fish, or for lining baking dishes or the rims of margarita glasses. Many professional chefs like to cook with it because they can measure it more easily with their fingers. Kosher salt and sea salt often come coarsely ground.