permaculture

[Marimike6@cs.com]

"Is all rockdust suitable for soil improvement? "

Ask them for an assay of the dust. They should be able to give you what's in 
it. Obviously some dusts have asbestos, cadmium or other problematic 
materials 
you wouldn't want to put into your vegetable garden. If they just tell you 
it's clean dust, that's not quite good enough, IMO.