Marble in pantries

[MrPahoehoe]

I'm really ashamed to be asking this as a geologist, but, I have a question about marble. I'm wondering about slabs of rock used in pantries before the days of fridges. Ok, so the pantry was constructed with the purpose of being a cold room and stuff that needed to be coldest (e.g. milk) was stored on the slabs of rock, which would retain the cold. Now, I was led to believe that these slabs were usually marble or sometimes limestone. However, I'm not 100% sure if this is true, but if it is then I'm at a loss as to why this is the case.

Marble and especially limestones are highly variable rocks, but can be quite dense. A denser rock would take longer to warm up and as marble is slightly denser than limestone it would make sense that marble be used. But I can think of denser rocks than marble (e.g. Basalt) and rocks with a lower specific heat capacity (e.g. Granite). Marble and limestone tend to be quite chemically pure, but I can't see how this would affect it, likewise: they are both made of calcium carbonate, but I know of no advantage that this would provide. Obviously these are very aesthetically pleasing when polished but I'm not sure if that is the reason, after all, its not like the guests would see in the pantry.

I would very much appreciate anyone who can shed any light on this. Thanks in advance MrP.

[MrPahoehoe]

Thanks for that Eddie, but I've already looked at stuff like that. What I was hoping someone might be able to tell me is; why was marble used for this purpose? What makes it a better choice?

Apparently marble is a cold surface, but can anyone tell me why it is colder than other rocks, cos as I said, it isn't the densest rock and it hasn't got the lowest specific heat capacity.

[MrPahoehoe]

Yes, surfaces will reach thermal equilibrium and attain the same temperature, thats not in doubt, but that doesn't explain why a marble work surface/floor will feel much colder than a carpet/piece of wood in the same room? Its to do with the rate of heat transfer (specific heat capacity). This is relevent in the pantry situation as the room is cold: so the slab will quickly reach room temperature and quickly take heat away from the objects to be cooled.

Limestone is a pretty common rock. Marble is fairly common also. Granite and basalt aren't as common generally. Having said this, some locations might be miles from a suitable calcium carbonate rock. Also, I was just using granite and basalt as examples: there are lots of other rock types that would be at least equally suitable as far as I can see. As I have said marble and limestone can have a really nice finish, which would be benefical for keeping food on and cleaning. But the way I had heard it told was that marble was almost always the rock used for this purpose. For me the reasons just don't seem to fit with response.

I suppose I might be wrong and other rocks might have been used. Can anyone please confirm or deny this? Or even better can someone tell me some properties of marble that I am neglecting.

[gammaray]

Marble was used in food preparation areas for example because it is easy to clean and can be polished to a very smooth surface. The effect of polishing a surface renders it cooler to the touch because as a polished surface it tends to reflect more heat than it absorbs naturally. It may be this that led people to use it in pantries.

[buckaroo2]

Just a thought, but wouldn't the choice of material depend on a combination of its properties, availability, processability and cost? Could it be that marble was in plentiful supply and was deemed the best compromise? There were undoubtedly materials that could have performed the task better but their advantage over marble could have been outweighed by their availability or cost.

[dyli795]

My Mothers pantry had a Granite stone shelf about 7" thick. (house built 1950)