Disclosed herein are diatomite filter aid products with enhanced permeabilities and flow characteristics, and methods for enhancing the permeabilities and flow characteristics of very fine grain, low permeability diatomite ore by, in one embodiment, pre-agglomerating the ore in the presence of less than 10% water and then subjecting the pre-agglomerated ore to at least one calcination process. At least one flux may be used in the at least one calcination process. Also disclosed herein is a method of processing diatomite ore suitable for samples with high wet densities or large amounts of fine particulate matter. Also disclosed herein are methods of producing commercially applicable filter aid products from Hungarian diatomite.