I like websites that are dedicated to one subject (like mine). David Bloch dedicated his website to Salt. In a chapter titled "Religion" I found his description (and pictures) of the usage of straws in the shape of the Star of David to produce salt. For example: in the days Israelites had been in exile in Egypt, before the exodus.
Another example (and picture) is from Andrews, A. P. (1983) "Maya Salt Production and Trade" (Univ. of Arizona Press, Tucson).