Vermiculite as a solo substrate

I stumbled upon this while hunting down chemicult articles....

http://www.youreinvited.co.za/?page_id=239
http://plantpropagation.com/propagationmedia.htm

How would this work as a solo substrate? Does anyone know the density and nutrient values?

 

it floats

 

Not all vermiculite floats, most of it sinks to the bottom when saturated(though you will always have a few stubborn pieces floating. The problem is, like peat, with the slightest disturbance its going to go all over the place, and it wont hold roots at all because of that. Here's an interesting link that I stumbled upon awhile ago:
http://aqualandpetsplus.com/Plant,%20Vermiculite.htm

 

Not all vermiculite floats, most of it sinks to the bottom when saturated(though you will always have a few stubborn pieces floating. The problem is, like peat, with the slightest disturbance its going to go all over the place, and it wont hold roots at all because of that. Here's an interesting link that I stumbled upon awhile ago:
http://aqualandpetsplus.com/Plant, Vermiculite.htm