Accordingly, a second embodiment of the invention is a method for producing a statistically large population of particles of amorphous precipitated silica having a glassy phase fraction in the range of from 0.3 to 30 area percent, the process comprising: (a) establishing an initial aqueous alkali metal silicate solution containing from 0.48 to 1.05 moles M2 O per liter and having an SiO2 :M2 O mol