I hope this is okay to ask here...
I ordered basalt dust but received fine granules instead. I know the dust will more quickly break down in the presence of the right microbes. Should I return the granules and order dust?
Im no expert but granules will be ok, it will be more of a slow gradual process of it breaking down and being available.
Rock dusts in general are slow release over few years, and are mainly micronutrients and are hard to over do. You might be able to use a few cups per cubic foot mix and be ok for a few years that way.
Or just crush them up.