Week of November 12, 2022

Through the Hourglass


Around the world, sand is different colors because that is the color of the rock or other material the sand eroded from. For example, black sand beaches are often made from eroded basalt from lava, and white sand beaches are often pulverized coral.


Ostriches don’t really stick their heads in the sand to hide from danger or problems, but they do put their heads down to dig holes for their eggs and eat plants.


By one prominent soil classification system, sand, by definition, must have grains between 0.074 mm and 4.75 mm. Smaller particles are silt, larger grains are gravel.


Sand is an essential ingredient in construction, with about 50 billion tons of it used in building yearly. At least seven different types of sand are categorized for various building purposes, including concrete sand, fill sand, and manufactured sand.


As plentiful as desert sand is, several factors make it undesirable for use in construction.


While there is spotty evidence that the world’s first sand-filled hourglasses were used by the ancient Romans and Greeks, it was more likely developed in Europe by the 8th century AD and certainly in widespread use on the continent six centuries later.


Think you’ve made some impressive sand castles? The world record largest sand castle was made in Denmark in 2021, measured just under 70 feet tall and was made of 6,400 tons of sand.