How does vermiculite lose and regain water molecules during dehydration?

[shalu]

vermiculite a mineral loss its water molecules when its is heated but it not loses it water molecules completely.how it is possible??

 

[jim mcnamara]

You are talking about water of hydration.

Example Si0_2 3(H_20)

google for water of hydration. Even oven drying to > 100C may not remove it.