For your consideration is this 12 sided clear quartz crystal vogel from Brazil. These are cut and polished by hand so are not perfectly calibrated. This one has internal rainbows, fairy spray and both terminations are Generators. It measures approximately 3.8 inches long and weighs 108 grams.
Clear quartz is known as the Stone of Power. Produces harmony of the body and mind, allowing one to think more clearly an act effectively. Increases physical and mental energy, perseverance, and patience re-directs negative energy to a positive state. Enables one to laugh and love more easily. Amplifies the energy of other stones, as well as amplifies the energy of intention.
Chakra: Crown