What is Coefficient of Thermal Expansion?
The Coefficient of Thermal Expansion is the rate of expansion of a natural stone (or any other material indeed) when it is exposed to a defined rise in temperature. A low Coefficient of Thermal Expansion will reduce the probability of thermal cracking in cladding materials that are exposed often to huge changes of temperature with in short timespan. The Coefficient of Thermal Expansion is usually measured in figures like this example: 6.1 x 10-6 K-1.
What is Thermal Conductivity Coefficient?
Most natural stones have a Thermal Conductivity Coefficient of above 2, and often even 3 W m-1 K-1. Glass, for example, usually has a Thermal Conductivity Coefficient of about 1 W m-1 K-1. Less thermal conductivity, of course has advantages especially when using a natural stone as outside wall cladding material as it increases insulation and thus reduces energy consumption.
What is Specific Heat Capacity?
The Specific Heat Capacity is the amount of heat (energy) required to raise the temperature of 1 kg of a substance by 1° K. The specific heat capacity of most types of granite is somewhere around 750 J kg-1 K-1, while the average specific heat capacity of marble is about 880 J kg-1 K-1.