Boulder

File:Balanced Rock.jpg

The Balanced Rock "balances" in Garden of the Gods in Colorado Springs, Colorado, United States.

In geology, a boulder is a large piece of rock fragment that is larger than 25.6cm or roughly 10.1 inches in diameter or with a size value less than -8 on the φ particle size scale with no upper size limit.

References

1. Webster’s New International Dictionary of the English Language. Springfield, Massachusetts: G. & C. Merriam Company. 1913.
2. "Boulder". Dictionary.com. Retrieved 24 August 2013.

Citations

1. "Boulder". Collins English Dictionary.

Other websites

• Media related to Boulders at Wikimedia Commons