By Richard Thomas
Heating stones in a fire is a classic article of Stone Age technology, long used to boil water and bake or roast in pits, and the sort of thing that routinely appears on Discovery Channel survival programming. The latest craze in whiskey accessories takes that notion and turns it around to create granite ice cubes, also sometimes referred to as whiskey stones. The idea is just as simple as hot rocks: take some stones, put them in the freezer, and then put them in your drink instead of ice cubes. For whiskey drinkers in particular, icing stones offer a handful of advantages over regular, water ice cubes.
Harsh, Jagged Ice
It is mid-July as I write this, and I am faced with my perennial problem as a whiskey lover, namely that whiskey of any stripe is a poor drink for summertime. The warming effects of whiskey clash severely with the heat of summer, so unless you live in an unnaturally air conditioned vault or in the cool, rainy, gloomy climate of Scotland, some of the effect of drinking neat whiskey is lost.
Some cope with this by drinking their whiskey on the rocks (indeed, some poor, deluded souls prefer it that way all year around), but that has a substantial downside. In my opinion the freezing cold of ice suppresses some flavors, while leaving others untouched. What flavors are pushed down by the chill varies from whiskey to whiskey, so there are no easy rules, such as “ice kills smoke.” Determining what whiskey works best with ice is therefore a matter of experimentation, or research through a source like The Whiskey Reviewer, who does the experimentation for you.
Experts will argue back and forth about the above assertion, but some other bad points of whiskey on ice are beyond dispute. First, the harsh chill of water ice also destroys the nose of a whiskey, as it plunges the temperature to far below the vaporization point of alcohol. Second, water ice melts, thereby diluting your whiskey with water you don’t want. Even if you like a splash of water in your whiskey, few whiskey lovers and no bars keep ice cubes made from branch water or distilled water, and tap water in your whiskey is a huge no-no.
Rocks in Your Whiskey
The obvious advantage of granite ice is that it won’t melt, and therefore won’t dilute your whiskey with unwanted tap water flavors. As I discovered, however, that is not the best part of using real rocks for your whiskey on the rocks.
Granite isn’t as conductive as water, so it doesn’t have the same chilling power. I found putting three or four granite ice cubes of the type made by Relaxhouse doesn’t have the freezing power of the same amount of ice. The granite mildly cools the whiskey, rather than harshly chilling it, leaving the nose and flavors intact.
Another obscure advantage of whiskey stones is they freeze quickly. Granite ice cubes are ready to go after 20 to 30 minutes in the freezer, whereas water needs hours to freeze into ice cubes. Being just a pile of cut rocks, whiskey stones are also easily washed and dishwasher safe.
The one drawback I found is that granite ice cubes won’t make anything ice cold, at least not unless you use many more cubes than the equivalent in water ice. To make a mixed drink freezing cold with rocks, you need to fill the glass with them. If granite ice cubes are a blessing for neat whiskey, they are a mixed blessing for the whiskey cocktail, where a drinker probably wants an ice cold beverage and dilution isn’t as big an issue.
Any Old Rock
A past question I have fielded about whiskey stones is “why can’t I use any old rock?” The answer is you can, but only after plenty of work. Whiskey stones are made of granite for a reason. Sedimentary rocks like sandstone and limestone easily wear down, both by rubbing against each other and because alcohol is a solvent. Limestone spring water might be an important ingredient in any whiskey-maker’s recipe, but who wants gritty bits of sand in their tumbler of whiskey? Marble and other hard forms of stone will work just as well, but avoid the soft, crumbly stuff.
After you collect the chunks of granite, you need to shape and polish them. Some rock ice on the market have a “natural” look, full of cracks and ridges. This style of whiskey stone is destined to crack open at some future date, since you will be sending them on repeat trips to the freezer and exposing them to the same forces that fill cliff faces with cracks and crevasses. Smooth, flat surfaces protect the stones from moisture and freezing, giving them a longer life span.
So, you can make your own whiskey stones, but only if you already own a stone chisel, hammer and a rock tumbler. If you don’t, you will find it much cheaper to simply buy a set of ready-made granite ice cubes.