These images were made on a compound microscope with an attached digital camera using polarized light and special light-retardation plates.
The crystals, of several different chemicals, were grown on microscope slides either from melted material or concentrated solutions in various solvents. Some of the crystals are so short lived that only one or two pictures can be made from a single preparation. Amongst the chemicals used to make them were, naphthalene and hexachlorethane (Moth repellant), Coldrex, (cold medicine containing vitamin C and Salicylic acid), Malic Acid -- found in most fruits, and also some ordinary chemicals such as potassium ferricyanide.
As a general rule microscopists who take pictures of crystals look for perfect ones or clusters, or junctions between adjacent growth, or twins and so on. When these images were made color and shape were the criteria used. Most of the bizarre images were made from crystals that were already dissolving again or evaporating in the case of naphthalene. It is these imperfect structures, that sometimes vanish in seconds, that make the most interesting pictures.
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