Is this stuff really as good as they say?
I have access to granite powder that is a byproduct of Stone Cutting and polishing.
Will this qualify as rock dust - much of it is as fine as powder.
Feed it to worms first?
When people say "rock dust" is this similar or the same as vermiculite?
Although not all vermiculite contains asbestos, some products were made with vermiculite that contained asbestos until the early 1990s. Vermiculite mines throughout the world are now regularly tested for it and are supposed to sell products that contain no asbestos. The former vermiculite mine in Libby, Montana, did have tremolite asbestos as well as winchite and richterite (both fibrous amphiboles) — in fact, it was formed underground through essentially the same geologic processes as the contaminants. A vermiculite mine in Virginia has also been found to be contaminated by asbestos.
Jen, you could maybe consider including some dynamic accumulators that would harvest and concentrate zinc, for example, mustards and sunflowers as mentioned in Gaia's Garden.
I'm extremely skeptical about the merits of rock dust simply because of the commercial nature of it (bagged product) and lack of empirical research/experimentation
It could very well be true though; anecdotally at least it seems that way. All I know is that I've been growing just fine without it