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Science in the City
Black Sand (Clip)
Date: August 9, 2011
Running Time: 00:03:53

Join Exploratorium educator Ken Finn as he unlocks the mystery behind the black sand (a.k.a. magnetite) at Ocean Beach. This piece explores the origin of magnetite in the Sierra Nevada mountains, its journey down the Sacramento and San Joaquin rivers to the Bay, and the interesting physical properties of this mineral, plus some fun things you can do with it.
Urban environments like San Francisco are full of mysterious natural and human-made phenomena. Why are there so many one-footed pigeons? Where does the sewage go? Why is our “summer” in May and September? The Exploratorium is “taking it outside" to explore these and other questions in engineering, ecology, optics, waves, geology, architecture, weather, and more. Look for new episodes once a month.