Water

The ancient Greeks developed the theory of the 4 elements to explain nature, including human nature and personality. This theory was refined by the Greek philosophers, Plato and Aristotle. Many who study astrology are aware that the astrological signs are attributed to the elements, which help explain our behavior.

Earth signs are grounded, loyal, patient, practical, very good at accumulating wealth which is helpful because they enjoy the finer things in life. However, earth signs can be very stubborn, inflexible, overly decadent, and lazy. 

Astrological Signs: Cancer, Scorpio, and Pisces 

Gemstones: Opal, Moonstone, Aquamarine Chrysoprase, Emerald, Pearl, Kunzite, Pink Tourmaline