Stone ball
A stone ball, or "stone sphere", is a spherical stone object that may be of either natural or artificial origin. Different types of stone balls include:
Natural
- Natural Stone Balls
- megaspherulites
- cannonball concretions
- Moqui marbles
- spherical corestones created by spheroidal weathering
Artificial
External links
- Stone round shot (cannonballs)
- Stone balls (spheres) of Costa Rica
- Carved stone balls of Scotland
- Hunterian Museum and Art Gallery, nd, Carved Stone Balls A gallery of carved stone ball photographs & information
- Marischal Virtual Museum, nd, ball, carved stone Aberdeen Museum's virtual gallery of their Carved Stone balls
- Megaspherulites
- Baird, Bill, 1990, Stone Spheres, The Edinburgh Geologist, no 24 (Spring)
- Heinrich, P.V., 2007, Megaspherulites. PDF version, 1.4 MB BackBender's Gazette. vol. 38, no. 7, pp. 8-12.
- Rodríguez, E.A., 2002, The fantastic balls in el Cerro Piedras Bola (Jalisco), México desconocido # 305, July 2002. Last visited February 11, 2008.
- Smith, R.K., R.L. Tremallo, and G.E. Lofgren, 2000, Megaspherulite Growth: Far From Equilibrium Crystallization, GeoCanada 2000 - The Millennium Geoscience Summit, Canadian Society of Exploration Geophysicists Annual Meeting.
- Smith, R.K., R.L. Tremallo, and G.E. Lofgren, 2001, Growth of megaspherulites in a rhyolitic vitrophyre, American Mineralogist. vol. 86, pp. 589–600.
- Cannonball concretions
- Hanson, W.D., and J.M. Howard, 2005, Spherical Boulders in North-Central Arkansas PDF version, 2.8 MB Arkansas Geological Commission Miscellaneous Publication n. 22, pp. 1-23.
- Heinrich, P.V., 2007, The Giant Concretions of Rock City Kansas PDF version, 836 KB BackBender's Gazette. vol. 38, no. 8, pp. 6-12.
- Irna, 2006, All that nature can never do, part IV : stone spheres
- Irna, 2007a, Stone balls : in France too!
- Irna, 2007b, Stone balls in Slovakia, Czech Republic and Poland
- Leo Gav, 2007, Underwater stone balls
- Hokianga Tourism Association, nd, Koutu boulders Really nice pictures of cannonball concretions.
- United States Geological Survey, nd, cannonball concretion