Granite

7-30 usd/kg
Circularity potential
Very high
Strength
Medium
Production energy
Ultra low
Stiffness
Medium
Embodied CO2
Ultra low
Density
High

Granite is an igneous rock (formed from magma) consisting mainly of silica (SiO2), feldspar and other minerals. It is quarried, cut into slabs and polished for use as worktops (countertops) and architectural surfaces.


Sustainability concerns
Non-renewable ingredients
Raw material generates polluting by-products
Low circularity potential


Granite is familiar as a mottled white, rose and grey ornamental stone. The appearance is graded, but as a natural material, no two pieces will be exactly the same. The inclusion of different minerals affects the colour and pattern, as well as mechanical properties. Feldspar is often pink, and so granite dominated by this mineral will appear mottled pink, for example. It is used as a worktop, countertop, kitchen counter and architectural solid surface material indoors and out.

So called ‘black granite’ is gabbro, a type of igneous rock, but that has cooled more slowly. It has different mechanical properties and is only available in dark-grey and black.


Design properties
Cost usd/kg
7-30
Embodied energy MJ/kg
5-10
Carbon footprint kgCO2e/kg
0.5
Density kg/m3
2540-3151
Tensile modulus GPa
20-60
Tensile strength MPa
7-25
Flexural strength MPa
13.1-30.1
Modulus of rupture MPa
11-16.3
Shear modulus GPa
20
Compressive strength MPa
95.5-310
Hardness Mohs
6.5
Poissons ratio
0.2-0.3
Thermal expansion (µm/m)/ºC
3.7-11
Melt temperature ºC
1600
Thermal conductivity W/mK
1.2-4.2
Temperature min-max °C
-250 to 500
Thermal
insulator
Electrical
insulator