How would I make a chemical flower garden?
6 tablespoonfuls of salt
6 tablespoonfuls of bluing
6 tablespoonfuls of water
1 tablespoonful of ammonia water,
and pouring, after thorough mixing, over a clinker, a piece of coke or of brick in a broad bowl or dish. After the clinker (or coke or brick) has been wet with the liquid, drop on it a few drops of mercurochrome solution or of red ink or green ink. But do not use iodine, because this reacts with ammonia water to form the dangerously nitrogen iodide, a black powder which is safe as long as it is wet but explodes with a loud report from very slight shock when it is dry. After the materials have been brought together, a coral-like colored growth soon begins to appear on the clinker. This increases rapidly. The growth also tends to form on the edges of the dish and will climb up and over them unless they have been rubbed with Vaseline. The growth will not extend beyond the Vaseline. The "depression flower garden" is a capillary phenomenon involving the tendency of ammonium salts to "creep." The saturated solution deposits crystals around its edges and upon the clinker where the evaporation is greatest. The crystals are porous and act like a wick, sucking up more of the solution by capillary action. The solution thus sucked up evaporates to produce more crystals, more wick, and more growth. The addition of
a little more ammonia water to the dish will produce more growth after the first growth has stopped. Or the whole may be allowed to dry and may then be kept without further change. The "mineral flower garden" which florists sometimes sell or display in their windows, depends upon an entirely different principle, that of osmosis or of osmotic pressure. A solution of sodium silicate or "water glass" is poured into a jar or globe, and crystals of readily soluble salts of certain metals which form colored and insoluble silicates are thrown in and allowed to sink to the bottom. Growths resembling marine plants spring up from these crystals and in the course of a few minutes climb rapidly upward through the liquid, often branching and curving, producing an effect which might lead one to believe that he sees exotic
algae growing in an aquarium. The experiment works best if the solution of water glass is diluted to a specific gravity of about 1.10.
Ferric chloride produces a brown growth;
nickel nitrate, grass green;
cupric chloride, emerald green;
uranium nitrate, yellow;
cobaltous chloride or nitrate, dark blue;
and manganous nitrate and zinc sulfate, white.
Source: The Chemical Formulary Bennett, H. v.1 Ref. 660.83 B471c
Also known as DEPRESSION GARDEN