Sand Is Defined by Grain Size, Not by Material
Sand is loose granular material. Geologists define it purely by how big the grains are.
Sand is loose granular material found on beaches, riverbeds and deserts. In geology it is a size category, not a substance: anything between 0.0625 and 2 millimetres across is sand, whatever it is made of. Most sand is quartz, but Hawaii has black basalt sand and green olivine sand, and much tropical white sand is ground coral and shell. Finer particles are silt, coarser ones gravel, and the word is Old English *sand*.
- Granular material. *Beach sand.*
- A size class. *0.0625 to 2 mm.*
- To smooth. *Sanding the wood.*
- Sandy — like sand. *Sandy soil.*
- Old English — *sand*. *The source.*
Word forms
| Form | Word | Example |
|---|---|---|
| Noun | sand | Sand. |
| Verb | sand | Sanding. |
| Adjective | sandy | Sandy. |
| Compound | sandstone | Sandstone. |
| German | Sand | Sand. |
- The sand was hot.Beach.
- Sand is a size class.Geology.
- He sanded the door.Verb.
Particle sizes
- Clay — under 0.004 mm
- Silt — 0.004 to 0.0625 mm
- Sand — 0.0625 to 2 mm
- Gravel — 2 to 64 mm
- Cobbles and boulders above that
Old English *sand*, of Germanic origin, related to Dutch *zand* and German *Sand*.
Is all sand made of quartz?
No. Sand is a size category. Hawaii has black basalt and green olivine sands, and tropical white sand is often ground coral.
How big is a grain of sand?
Between 0.0625 and 2 millimetres. Smaller is silt, larger is gravel.