Most on the market are made of non-porous materials, such as soapstone, granite, or (not a stone) stainless steel. They're stored in the freezer, then placed in a glass of whiskey as you would ice.

Whiskey rocks are ice-cube-sized blocks that can be made of marble, granite, or similar stone-like materials or even stainless steel. One of their most important properties is that they are non ...