Fig. 5

Custom made analytical and experimental equipment. a Teflon^© plate used for the colour measurements with a granophyre sample positioned in the centre. The markings on the outer ring were used to turn the chromameter by the same angle during each measurement. b Teflon^© containers used to collect water samples during the artificial sprinkling experiment. The containers have a removable cover with a hole in the middle and a small base in the middle for the rock samples. c Holder for the PXRF used to ensure a reproducible positioning of the samples for every measurement. The holder consists of an acrylic glass case with a height adjustable sample stage on which the samples can be fixed. The PXRF is held in position by four plastic screws on the sides. The inset in the upper left corner shows the measured area (spot size) of the PXRF, measured with an X-ray film, on a superimposed μCT scan of a gabbro sample