calcium-rich

...the "zir"...the Jordanian version of the water cooler. Water was hauled from the town spring to a cistern at the building where we stayed. Then, the water we drank was boiled and put in these ceramic pots. "The latent heat of evaporization," (a catch phrase that never got old, or true) cooled the water. We dipped the coffee cup into the zir and filled our water bottles. In other words-- grimy, sunscreened hands went in and out of this water, bugs floated in it, and calcium collected in it. Yummy.