Sand Collecting [dot] Net

the hobby of sand collection

What is sand?


about sand
Sand is a naturally occurring material composed of minute rock and mineral particles. A single particle of sand (a grain of sand) ranges in size from 1/16 mm to 2 mm. The next size up from a sand particle is called "gravel", while the next smaller size is called "silt". When it is handled, sand has a distinctive gritty feel.

Size your sand

For collection and display purposes, it can be useful to sort one's sand by size. This makes for a nice, uniform display. Sand can be classified by the size of the particles:

The Colours of Sand

It may come as a surprise to you, but not all sand is "sand-coloured." The colour of any particular grain of sand is determined by its chemical composition. A microscope and a good crystal identification book may be helpful in identifying the type of sand you have. The most common type of sand is made of silicon dioxide (usually quartz). These grains are clear or opaque.

White sand is formed from eroded limestone. Black sands are volcanic, as are green sands composed of olivine. In some areas, sand is primarily crushed seashells (calcite), which gives a pinkish cast.

Colour Type
clear quartz (from granite or sandstone erosion)
dull black, grey, or reddish-brown basalt
olive-green or brownish olivine (from basalt erosion)
black (shiny irregular shapes) obsidian (from basalt erosion)
clear, yellow, or pink feldspar
light-coloured or pink granite
dark pinkish garnet
transparent white gypsum
red hematite
yellow or brownish monazite
shiny black and magnetic magnetite
white, tan, or pink carbonate (from shell erosion)

In addition to the mineral-based sands, there are also biogenic sands which contain the remains of animals and plants, shell fragment, tiny skeletons, micro-mollusks, and other sea creatures often almost too small to see by the naked eye. These remains are called "foraminifera".