We don't work with crystals in the gnostic tradition because those elementals are simple in comparison to the evolved souls of the plant kingdom. Plants carry more power to influence nature and the mind, which is why Samael Aun Weor dedicated two books to the subject: Igneous Rose and Esoteric Medicine and Practical Magic. The closest thing we get to using elementals from the mineral kingdom are pentagrams with the seven metals: silver, mercury, copper, gold, iron, tin, and lead, representing and containing the forces of the seven archangels and seven mighty spiritual rays: Moon (Gabriel), Mercury (Raphael), Venus (Uriel), the Sun (Michael), Mars (Samael), Jupiter (Zachariel), and Saturn (Oriphiel).

The majority of practices (available on the internet) that utilize minerals or crystals are forms of black magic, because minerals and crystals relate to the submerged mineral kingdom, Klipoth, which is easily accessed and influenced through negative arts.

Learn more how to charge talismans or pentagrams with the seven metals in the opening of The Pistis Sophia Unveiled and the end of The Major Mysteries.