Whiskey Stones also called Stainless Steel Ice Cube,are ideal for drinking with high quality whiskey because they keep it at the perfect sipping temperature (50 degrees), whereas ice cubes can make the whiskey too cold and ruin the flavor.
These stones, available in a variety of sizes, are designed to be stored in the freezer, and added to Whiskey Stones in a Glassstraight shots of whiskey, bourbon, or scotch, in order to chill them without the risk of diluting the drink.
Temperatures in the high 30s are far too cold for good whiskey. Reason being that the wood oils in the whiskey, which have leached into the liquid from the carefully selected cask it was aged in and which carry all the flavor, tend to congeal and "close down" the flavor of the drink itself when the temperature goes below 50. The Whiskey Stone are specifically designed to "take the edge off without diluting or closing down the flavor."