> Don't discard the opportunity to rebuild your soils with rock dusts if
> it can be done cost effectively. If the source is local and transport
> costs are low then give it a go. Trials we have carried out with
> farmers have definitely demonstrated the benefit.
> Know your rock type, don't choose mono minerallic rocks such as quartz
> thinking they will contain a broad range of minerals. Ask a geologist or
> your quarry manager what the rock type is and access material which has
> the consistency of talcum powder. The finer the powder the greater the
> surface area that can be attacked by soil acids.
Many quarries in the US use multiple settling ponds to facilitate
recycling of wash water. They periodically use a crane and clamshell
bucket to dredge these ponds. This mined silt is extremely fine and clean
and is perfect for remineralizing farm soils. Often this material is given
away for the hauling.