For the Celestial Exalted, a caste mark is a distinctive mark that, like the anima, is normally invisible. It appears on the forehead as the Exalt spends Essence. The mark identifies their caste for all to recognize one of the Chosen.
The mark varies for the different Exalted. No two types of Exalted share a caste mark, so they may be used to distinguish one type of Exalt from another. Solars have a golden circular image of the Sun as it travels through the sky, while Abyssals have a similar image, only black and bleeding. Lunar Exalted have a silver caste mark which represents a phase of Luna. Finally, Sidereal Exalted have the astrological symbol of their patron Maiden in the color of their caste.
Terrestrial Exalted have no caste mark, instead being marked by ambient anima effects (and at higher essence, their appearance). Alchemical Exalted have no caste mark either, although the caste is generally identifiable by the magical material from which they are composed.