Fig. 1. Collection of datasets from the pseudo bulk experiment with SI_(initial) = 2.8.

a Experimental setup; b optical micrograph of barite crystals after three minutes; c Raman spectra collected during the experiment; d zoom on the intensity of the SO₄²⁻ signature bands with ν₁ and ν₃ corresponding to the symmetric and the anti-symmetric stretching mode respectively, and ν₂ and ν₄ corresponding to the bending vibrations³. The water bands indicated refer to the H-O-H bending mode at 1648 cm⁻¹, and the symmetric and anti-symmetric O-H bands at 3280 and 3410 cm⁻¹, respectively.