Is sand a liquid ( because it flows ) or solid ( like an individual piece )?

Question: Is sand a liquid ( because it flows ) or solid ( like an individual piece )?
- Keywords:
  liquid,
  sand,
  solid,
  state
Asked by nine45pie to Souvik, Sabine, Maria, John, Faye, Armin on 14 Nov 2019.
- Souvik Kundu answered on 14 Nov 2019:
  
  Sand is solid. It is so small and the light that it flows with the water or wind.
- Maria McNamara answered on 17 Nov 2019:
  
  Sand is a solid. The confusion arises because of the language we use for how very small particles move. A suspension of sand in water, though, is a liquid. And quicksand is a non-Newtonian fluid, meaning that its viscosity changes under pressue. In particular quicksand behaves as a solid under sudden high pressure and as a liquid under steady pressure.

Question: Is sand a liquid ( because it flows ) or solid ( like an individual piece )?