Chemical-garden formation, morphology, and composition. I. Effect of the nature of the cations.

We have grown chemical gardens in different sodium silicate solutions from several metal-ion salts--calcium chloride, manganese chloride, cobalt chloride, and nickel sulfate--with cations from period 4 of the periodic table. We have studied their formation process using photography, examined the morphologies produced using scanning electron microscopy (SEM), and analyzed chemical compositions using X-ray powder diffraction (XRD) and energy dispersive X-ray analysis (EDX) to understand better the physical and chemical processes involved in the chemical-garden reaction. We have identified different growth regimes in these salts that are dependent on the concentration of silicate solution and the nature of the cations involved.