From Mocha:

“Nordic Rock is mined from ancient Swedish pollution-free base rock. It is the purest way of cooling your drink - literally ‘on the rocks’. Stone does not melt, which means no unclean water in your glass. They are also reusable making them very eco-friendly.

To use, simply place the stone ice cubes in the freezer for approximately one hour before use. For a normal glass, two or three Nordic Rocks will be fine. They give off their cold gradually and equally.”

16 pounds