In essence, calcite splits a beam of light into two dots based on polarization. By aligning filters and rotating angles, you can observe how light behaves when forced into ‘choices’.

These can affect its color, giving it a range of hues, including blue, green, red, lavender, black ... calcite." Calcite also fluoresces in many different colors under ultraviolet (UV) light.

62, No. 2 (2017), pp. 645-664 (20 pages) Characterization of autochthonously produced calcite particles, along with the associated heteronuclei, and evaluation of their effects on light scattering, ...