-The coniunctio (union/conjunction) of Sol and Luna is often called the chymical wedding

-The union of Sol and Luna is often compared to the "marriage" of Christ and the Church

-The coniunctio is one of alchemical fundamentals: the union of body and spirit (Jung’s and Pauli’s psycho-physical monism theory)

-The product of coniunctio is always Mercurius - the epitome of balanced opposites (The Sun and the Moon are said to supply seeds to plant in earth, from which Mercurius grows)

-The relationship between the Sun, the Moon, and Mercurius is referred to as coniunctio triptativa

-Sol and Luna most frequently symbolize consciousness and the unconscious, respectively

-Fiery Sol, the Sun, whose corresponding metal is gold (or sulphur), is the source of warmth and light (gold was often called "the sun in the earth")

-Watery Luna, the Moon, whose corresponding metal is silver (or salt), is dark and cold (water and spirit are often identical; water also holds death-rebirth symbolism)

-Sol and Luna are equivalent to the Yang (positive, male, assertive) and the Yin (negative, female, receptive) in Taoist philosophy, whose reciprocity is the reason for all events of the universe

-Sometimes the coniunctio is seen as the union of sacred incest, omnipresent in world mythologies: as fiery gold, Sol is the result of the alchemical transmutation, and as watery Prima Materia, the spiritus aqua, Luna is its origin. This makes Luna the mother of Sol

-Luna and Sol often appear as White Queen and Red King (note these colors’ corresponding stages of transmutation; the symbol of this relationship is a rose). This relates to their symbolism as the anima, the female principle within a male personality, and the animus, the male principle within a female personality, respectively. (Jung called this aspect a "medium between the ego and the unconscious). This is reminiscent of Rubedo, in which Luna becomes a man, whereas Sol becomes a woman. According to Jung, both aspects are crucial to their corresponding Self, and their realization is achieved through relationships with people of the opposite sex. The alchemical concepts of Sol and Luna seem to be the unconscious projections of the animus and the anima

- Luna is often called Anima Mundi, the World Soul which surrounds cosmos, half-human half-animal Melusina, or even Lilith. (see dictionary) As Melusina, she is similar to Virgo, who is often associated with the Mercurial Serpent. As the Moon, Melusina is also compared to Venus or Aphrodite, not unlike Mercurius. Similarly, Melusina as Lillith, is the first wife of Adam in Paradise, whereas Mercurius is often associated with Adam before the Fall. It is only natural to represent Mercurius as the anima, which alchemists often did.