Ordinary table salt can be an interesting subject, depending on the lighting conditions. First, we see two images of a strew at 5x, then a single crystal at 10x with Disco Lights Illumination.
Next, the color filters are removed, but the darkfield illumination remains.
Then, we see them with crossed polarizers, first in brightfield, then darkfield is shown.
We now turn our attention to 4x tranmitted Rheinberg, with five different combinations of colors.