Ooid
spherical sedimentary grains
An ooid is a small rounded sedimentary rock. Like sand grains, ooids have a diameter of 2 mm or less. Larger grains formed the same way as ooids are called pisoids. Rock made of ooids is oolite.[1]
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/9f/Ooids%2C_Joulter_Cays%2C_Bahamas.jpg/220px-Ooids%2C_Joulter_Cays%2C_Bahamas.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/c/cd/OoidSurface01.jpg/220px-OoidSurface01.jpg)
![](http://upload.wikimedia.org/wikipedia/commons/thumb/7/76/CarmelOoids.jpg/220px-CarmelOoids.jpg)
References
change- ↑ "Ooid Sand - Sandatlas". www.sandatlas.org. Retrieved 2022-04-16.