Sand & gravel
Loose rock grains dug from rivers and glacial deposits that become concrete, asphalt and road base: the bulk of all mined material.
Construction · No. 79
- Not on a critical list
Sand and gravel are the most mined materials on Earth, yet no one can say how much the world digs.
Chart: Illustration: Sand & gravel
Where it comes from
Chart: Map of where it comes from
Water and ice sort rock into loose grains in rivers, floodplains and glacial deposits, which are dug from pits or dredged from offshore banks.
Three things to know
- Smil puts world use of sand, gravel, clay and stone at around 40 Gt a year, yet no world total exists.
- Singapore reported 600 million t of sand imports over 2000-20, while exporters reported only 280 million t.
- Desert sand is mostly useless for concrete, because rounded wind-blown grains behave differently from angular or river sand in a mix.
The journey
- 1 Rivers and iceGlacial deposits, river channels, floodplains
- 2 Pit or dredgeExcavated on land or dredged offshore
- 3 WashingWashed and screened by grain size
- 4 StockpileHeld at the pit or yard
- 5 ConstructionConcrete, asphalt, road base and fill