Vermiculite is a hydrated phyllosilicate that undergoes strong expansion when heated. This phenomenon is known as exfoliation. It is formed by atmospheric agents or by the hydrothermal alteration of biotite or phlogopite. There are currently large commercial mines of vermiculite in the United States, Russia, South Africa, China and Brazil. It was first described in 1824. Its name derives from the Latin vermiculare, "to breed worms", for the way it exfoliates when heated.
Dimensions
Height (cm): 4.5
Depth (cm): 4.3
Width (cm): 6.1
Weight (g): 168
Property
Chemical Formula: (Mg, Fe2 +, Fe3 +) 3 [(Al, Si) 4O10] (OH) 2 4H2O
Mohs scale: 1.5–2
Relative density: 2.4–2.7
Crystalline System: Monoclinic
Note:
The base is included in the price. Piece shipped on base as shown in photos.