Why does Dubai import sand from Australia?
To make the Bhurj Khalifa, Dubai had to import sand from Australia.
I hope you see the irony in this — Dubai, a desert city surrounded by sand — has to import the same thing from across the world!
Desert sand is clearly different from other types of sand — particularly the ‘river sand’ that’s used for construction.
The difference is in the shape of the sand grain.
The sand in the desert is constantly tossed around by wind and keeps rubbing with each other. The result is that these grains are round and quite smooth.
River sand — at the bottom of the river — is coated with a thin film of water. This protects the grains from too much abrasion, keeping them pointy and sharp.
The result is that river sand locks together better, creating stronger mortars for buildings.
Sand is a very curious substance.
Sand is formed from the weathering of rocks such as granite or sandstone. Now, these rocks themselves could have been made from sand that either melted or solidified over millions of years.
In fact, the sand that we see today is thought to have gone through at least six such cycles of birth and rebirth!
The samsara of sand!
Read my article on sand here: http://ow.ly/xUDO50Dgclx
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