Chemical gardens grow when a metal salt crystal is placed in sodium silicate (waterglass) solution. A semipermeable metal silicate membrane forms instantly around the crystal. Osmotic pressure drives water inward, building pressure that ruptures the membrane and squirts metal-ion-rich solution upward, where it immediately re-precipitates as a silicate tube. The result: hollow, walled tubes that grow upward driven by buoyancy and osmosis.
The simulation models each tube tip as a biased random walk with occasional branching. The colorization reflects metal ion concentration: iron(III) → orange/rust, cobalt → blue, copper → teal, nickel → green. Chemical gardens are studied as models of early Earth hydrothermal vents, protocell membranes, and even early metabolism. The spontaneous self-organization from simple chemistry exemplifies dissipative structures in the sense of Prigogine.