There are different fineness grades available. YES, wear a dust mask if using the finest powder (which will 'feed' your soil quickest). The dust mask is not needed if using the 'granulated' grade (which is a slower release).
Personally, I believe that most soils would improve greatly with an application.
Besides feeding the plants, it will also feed the soil food web.
The soil is like a chain: its weakest link is the one mineral that is lacking.
Try to find a local distributor, as 44# bags are not what you want to pay shipping on.
Shop around...prices vary greatly.
My source has fine for $16, granulated $20 (for the 44# bags). I have seen it $45 + S/H
I had to look it up also . Combination of sea and volcanic minerals. It is also being used as supplement in poultry/livestock feeds. I wonder if anyone is using it the way Salatin uses Fertrells Nutri-Balancer?
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