Metachromatic granules contain RNA and polyphosphates They are deeply stained with aniline dyes。They are characteristic features of the corynebacteria.
Protein crystals, large or small, can be stained with Mercury bromphenol blue, Amido black 10B and Coomassie brilliant blue R250 or G250 but salt crystals are not.
Doors and windows of Cedro wood, marine plywood panels and cedar bifold shutters are all stained for uniformity and mimic the color of the brick on the original building (dating back to 1926).