What can a grain of sand tell you about the Earth?

Station	Color	Magnetite	Size	Texture	Wentworth	Sorting	Comp.
Maui	mixed	yes	1.5 mm	rounded	sand	well	rocks
Klamath	black	no	1.5 mm	angular	sand	moderate	rocks
Hampton	light	no	1 mm	angular	sand	moderate	rocks
Salinas	light	no	.3 mm	angular	sand	very well	rocks
Edgartown	light	no	1 mm	subrounded	sand	moderately	rocks
Virgin	light/black	no	.1	angular	sand	poorly	rocks
St. Martin	light	no	varies	angular	sand	very poor	rocks
Pine	light/clear	no	.1	subrounded	sand	well	rocks

The “Maui” sand must be from a beach with very high-energy waves because of its rounded shape. It must be from a marine source because there are no holes that hint at a volcanic origin, plus the colors are mixed, which means it could be accumulated from/traveled from many different places. The round edges are another hint at a long journey for this sand. Since it is well-sorted, it must be from the water, since water naturally sorts based on size and density.

The “St. Martin” sand must be from a calmer beach because it’s angular and less broken down than the Maui sand. The variety of surface features and textures hint at a variety of sources- most likely land-based due to the poor sorting and harsh texture. The size also varies greatly. It is unlikely for this sand to be from the ocean because water sorts very well/usually rounds off the grains.