More biomineralisation….

Finishing off my experiments in Jerusalem. The right image shows the aragonite skeleton forming under the coral tissue (visible as a grey film just covering the crystals) and the left image shows the distribution of the dye calcein (bright = dye, dark = no dye). Calcein is membrane impermeable and it is present in seawater (bottom left corner) and where seawater has been transported under the tissue (bright ends of some crystals).