And so far everything I have pontificated has been a total swag as well though not because of fear of the truck. I think the reason you get an extra point for a mathematician is we tend to be just a bit lazier (the proof of this is trivial and left to the reader as an exercise). I did say that over the small temperature range of any practical method heat of fusion would far and away dominate the calculation. If no state changes are involved though material will make a difference and even though mass might be a good first order approximation what it's made of will have a significant effect as well. Just intuitively I suspect going metallic would be a bad choice. Even though they are quite dense the have very very low specific heats. Conductivity is really more about how quickly it can pull all the heat it's going to out of the whisky before it starts it's climb back to room temperature rather than how cold it will make it. It's not obvious to me whether this is a plus or not and shape of the ersatz ice most likely has a bigger effect on it anyway. If it is a positive though we should probably look at using diamond which has an even higher conductivity than steel. I don't think you deserve the full three points until I do the other materials and get a real value for the liquid nitrogen but I did look up stainless to compare against water which I didn't need to look up. 7.5 - 8 g/cm³ and 0.11 cal/g °C for 0.82 - 0.88 cal / cm³ °C as opposed to water's 1.0 cal / cm³ °C. Ice would be a little less dense but even without its heat of fusion probably still has a slight edge. Obviously the colder you can make something the more a small 10 - 20% difference will make.
The cocktail weenies obsess over this stuff, for example in this article.
Conductivity is really more about how quickly it can pull all the heat it's going to out of the whisky before it starts it's climb back to room temperature rather than how cold it will make it.
There's a sweet spot somewhere that I assume actual ice probably hits best. If you did have a material that you could chill enough to approximate the amount of cooling a similar amount of ice would provide... it would do its work faster than ice because of the temp difference (at first), and then soon stop having much effect at all. Ice would also shed a lot of water at first fairly quickly, then slow as the drink cooled but would continue to melt for several minutes maybe, helping to fight the upward creep in temps as the glass and drink take in heat from your thumb etc. Once the stones have been in your drink for a few minutes, you might as well fish them out (with a chilled spoon) and return them to the freezer.
But if you're using ice or stones to lower the temp to something less than bathwater, you're storing the stuff wrong (see: Islander, 2015). If you need some dilution, do what you need to do. If you're interested in combatting the upward creep toward lukewarm once poured, and you want it diluted, ice is your answer. If you don't want it diluted and want to maintain a cool temp, you might want to carve your rocks glass out of a 3# block of marble and keep it and the bourbon in the cellar on Islander's boat.
How about considering the impact of a massively porous material like lava rock, or an aerogel?
I think that is just effecting the rate of heat transfer and is what I was talking about when I said shape would have a bigger effect than conductivity.
Edit: Although if you want to account for the cold air innitially inside the stone escaping into the atmosphere it does complicate the problem
And so far everything I have pontificated has been a total swag as well though not because of fear of the truck. I think the reason you get an extra point for a mathematician is we tend to be just a bit lazier (the proof of this is trivial and left to the reader as an exercise). I did say that over the small temperature range of any practical method heat of fusion would far and away dominate the calculation. If no state changes are involved though material will make a difference and even though mass might be a good first order approximation what it's made of will have a significant effect as well. Just intuitively I suspect going metallic would be a bad choice. Even though they are quite dense the have very very low specific heats. Conductivity is really more about how quickly it can pull all the heat it's going to out of the whisky before it starts it's climb back to room temperature rather than how cold it will make it. It's not obvious to me whether this is a plus or not and shape of the ersatz ice most likely has a bigger effect on it anyway. If it is a positive though we should probably look at using diamond which has an even higher conductivity than steel. I don't think you deserve the full three points until I do the other materials and get a real value for the liquid nitrogen but I did look up stainless to compare against water which I didn't need to look up. 7.5 - 8 g/cm³ and 0.11 cal/g °C for 0.82 - 0.88 cal / cm³ °C as opposed to water's 1.0 cal / cm³ °C. Ice would be a little less dense but even without its heat of fusion probably still has a slight edge. Obviously the colder you can make something the more a small 10 - 20% difference will make.
How about considering the impact of a massively porous material like lava rock, or an aerogel?
Not looking anything up either (don't want to get hit by a truck). I think the latent heat of fusion would be the major driver. It's the state change that takes all the energy. Between Stone and Steel i think you'd really just be looking at mass, I doubt the difference in conductivity would matter much.
All in all, I just keep the bottle in a cabinet that stays cool, and if it's over 90 I'll probably be drinking a frozen something anyway.
And so far everything I have pontificated has been a total swag as well though not because of fear of the truck. I think the reason you get an extra point for a mathematician is we tend to be just a bit lazier (the proof of this is trivial and left to the reader as an exercise). I did say that over the small temperature range of any practical method heat of fusion would far and away dominate the calculation. If no state changes are involved though material will make a difference and even though mass might be a good first order approximation what it's made of will have a significant effect as well. Just intuitively I suspect going metallic would be a bad choice. Even though they are quite dense the have very very low specific heats. Conductivity is really more about how quickly it can pull all the heat it's going to out of the whisky before it starts it's climb back to room temperature rather than how cold it will make it. It's not obvious to me whether this is a plus or not and shape of the ersatz ice most likely has a bigger effect on it anyway. If it is a positive though we should probably look at using diamond which has an even higher conductivity than steel. I don't think you deserve the full three points until I do the other materials and get a real value for the liquid nitrogen but I did look up stainless to compare against water which I didn't need to look up. 7.5 - 8 g/cm³ and 0.11 cal/g °C for 0.82 - 0.88 cal / cm³ °C as opposed to water's 1.0 cal / cm³ °C. Ice would be a little less dense but even without its heat of fusion probably still has a slight edge. Obviously the colder you can make something the more a small 10 - 20% difference will make.
How much you can bring the temperature down is mostly about the total heat the cold substance can take out of the warmer whisky before thermal equilibrium is reached. I suspect that any heat loss through evaporation is negligible and the difference made by diluting even less. The real determining factors are the mass and specific heat of the cold stuff plus in the case of the ice the latent heat of fusion. I am still trying to avoid actually looking up numbers and doing calculations but the liquid nitrogen was a bit of an over statement. As Scott said over the range from the ice box to equilibrium temperature heat of fusion is going to be the dominant factor. Even without it though there aren't many things with a higher specific heat water either. I should really have been thinking about specific heat times density to get the heat for equal volumes of ice and stone as opposed to equal mass though. I would guess water still has the edge but they're on the same order of magnitude. Without looking it up I would guess Scott's stone or some specialized glass or ceramic would be a better choice of material than miami's stainless steel. Not knowing for sure is what may eventually drive me to looking up the actual numbers. Back when I was in college and had a Swede for a roommate we always had a bottle of aquavit in the freezer and generally a few shot glasses as well just to keep that much colder. I'm kind of a cube man myself but I would think a small glass with thin walls and a thick bottom might be just as good a thing for the purist to keep in the freezer as anything else.
Not looking anything up either (don't want to get hit by a truck). I think the latent heat of fusion would be the major driver. It's the state change that takes all the energy. Between Stone and Steel i think you'd really just be looking at mass, I doubt the difference in conductivity would matter much.
All in all, I just keep the bottle in a cabinet that stays cool, and if it's over 90 I'll probably be drinking a frozen something anyway.
Dinner was fine; too much tzatziki, and that wasn't as interesting as I'd like. I thought it needed more garlic and/or pepper but that might not be authentic. But mostly it was good but messy. There was also too much meat, which is a weird "complaint," but the onions, tomatoes etc were overwhelmed. I appreciate him trying to give us our money's worth but you can't forget your ratios...
That's the point of the thin walls. They would heat up first even if you get it very cold and the more massive base takes a little longer to completely warm up
Uncle.
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Dinner was fine; too much tzatziki, and that wasn't as interesting as I'd like. I thought it needed more garlic and/or pepper but that might not be authentic. But mostly it was good but messy. There was also too much meat, which is a weird "complaint," but the onions, tomatoes etc were overwhelmed. I appreciate him trying to give us our money's worth but you can't forget your ratios...
Talk about your nerd sniping: Thin walls? So you'd handle this with gloves then?
That's the point of the thin walls. They would heat up first even if you get it very cold and the more massive base takes a little longer to completely warm up
PSOB's Fault. Kind of like Aesop's Fables but with bacon.
For me it's got to be sausage with flapjacks, because real maple syrup. 
Oh yeah I got overruled by the new food truck. But there's bacon in the fridge...
Dinner was fine; too much tzatziki, and that wasn't as interesting as I'd like. I thought it needed more garlic and/or pepper but that might not be authentic. But mostly it was good but messy. There was also too much meat, which is a weird "complaint," but the onions, tomatoes etc were overwhelmed. I appreciate him trying to give us our money's worth but you can't forget your ratios...