Australia's Science Forum

We grow crystal gardens in sealed specimen containers. A dilute sodium silicate solution with a tiny bit of several different coloured metallic chemicals dropped in. Another is Potash Alum (Aluminium Potassium Sulphate) saturated with the seed crystal as an option as well as the standard CuSO4 one,(always wear safety glasses with CuSO4 as can damage the eye if it splashes). Lead acetate in a test-tube with a zinc strip is a quickie (Teacher dispensing the lead soln if you're worried). And there's a top year 11 prac growing metallic crystals in an agar-agar jelly containing one of these solids AgNO3, Pb(NO3)2,CuSO4 or SnCl2 poured over a zinc strip in a petrie dish (with a lid). I think the AgNO3 is the best, from memory. Heinemann chem one 1990.Crystals is my favourite prac.