i dont want to indicate all silicates are bad for

i dont want to indicate all silicates are bad for fert-some are fine but the high concentration of certain silicates and other adverse elements in most usa iron is contraindicated for fert i believe -cat guarantee as its hard to find info on these subjects but the above -whatever adverse elements are in most usa fert -logically is a reason fert is rarely at least publicly linked to iron mining