Lycopodium powder
Although there is only one formula I know that calls for this chemical, there are other reasons to buy it. The powder can be sprinkled onto a water surface, to increase the surface tension dramatically, you can also roll beads of water in the powder, which can then be rolled over the surface of the lycopodium coated water.
Colour: Pale yellow
Odour: Odourless
Solvent: Insoluble in most solvents