At One Place

Granite

Density of granite
2,700 kg/m³ (2,600–2,800)
2.70 g/cm³ · 168.6 lb/ft³

A coarse-grained igneous rock of quartz, feldspar and mica, which is why it is hard enough to resist knife scratches on a worktop — the quartz grains are Mohs 7. It is strong in compression, at over 100 MPa, and weak in tension, at 7-25 MPa, like all stone. Machine tool surface plates are granite rather than cast iron because it does not rust, does not raise a burr when scratched, and is dimensionally stable over decades.

Properties

Density
2,700 kg/m³ (2,600–2,800) — 2.70 g/cm³
Tensile strength
7–25 MPa
Young's modulus
50 GPa
Thermal conductivity
2.9 W/(m·K)
Hardness
6 Mohs
Thermal expansion
8 µm/(m·K)
Floats in water
No
Magnetic
No

What it is used for

  • Kitchen worktops and vanity tops
  • Kerbstones, setts and paving
  • Machine tool surface plates
  • Monuments and cladding

How it compares

Water is 1,000 kg/m³. Anything with a shorter bar than water floats in it.

air 1.2 kg/m³
expanded polystyrene foam 20 kg/m³
rigid polyurethane foam 40 kg/m³
Water — the float line 1,000 kg/m³
granite 2,700 kg/m³
tungsten 19,250 kg/m³
gold 19,300 kg/m³
platinum 21,450 kg/m³
Water is 1,000 kg/m³. Anything below that floats.
Material Density Relative to water
rigid polyurethane foam 40 kg/m³ 0.04×
expanded polystyrene foam 20 kg/m³ 0.02×
air 1.2 kg/m³ 0.00×
granite ← 2,700 kg/m³ 2.70×
platinum 21,450 kg/m³ 21.45×
gold 19,300 kg/m³ 19.30×
tungsten 19,250 kg/m³ 19.25×

Does it rust?

Granite contains no iron, so it cannot rust. Whether it degrades depends on the material, not on oxidation.

Is it magnetic?

Granite is not a metal and has no ferromagnetic response.

Common questions

What is the density of granite?
2,700 kg/m³ (2,600–2,800), or 2.70 g/cm³.
Does granite float?
No. At 2,700 kg/m³ it is denser than water.
Is granite magnetic?
Granite is not a metal and has no ferromagnetic response.

Related pages

Sources

  1. United States Geological Survey — USGS (Public domain (US Government))

How these figures are compiled and checked