the number five does not occur in the classification of natural crystal systems: thus there is no hardening of form at the basis of five. Five loosens, and in a sense it also has something revolutionary in it.
Hamaker-Zondag establishes five as the number of structural non-fixity and revolutionary dynamism, grounded in the empirical absence of fivefold symmetry in natural crystals, and identifies it with the human pentagram and with Eros-Lilith energy in the Tarot Minor Arcana.
, Tarot as a Way of Life: A Jungian Approach to the Tarot, 1997thesis