Ann: Phosphate Bioavailability Test Results, page-16

Regarding light capital works for the phosphate.

at min and best probability it would require,

a dozer
a screener
several loaders with in build loadweights
several loading ramps

might need a crusher mill.

this is how lime pits are run in Australia.

purchaser comes in with a truck gets filled and drives off .

this is organic product as it's not synthetic fertilizer so would seek a premium, and it not as acidic in nature .

for example Mop is an acidic potassium sells less than half the price of SOP which is a more natural brine type potassium, I'd assume natural phosphate would also have a higher value