The pigment cells called chromatophores determine the color of an axolotl. There are mainly three types of chromatophores causing different color pigmentation – Iridophores – Contains Crystalized Purines causing a shiny soap-bubble type of pigmentation (Iridescence)
Lanthophores – Contain Lanthanoid Compounds that cause a muddy sort of pigmentation (Moorings)
Absorption Chromatophores – These don't change color but allow light to be absorbed, changing the axolotl's overall shade (Black & Dark Brown Axolotls)