Agate is not a traditional birthstone associated with any specific zodiac sign, but it is believed to have metaphysical properties that can be beneficial for people born under various signs of the zodiac.
In general, agate is thought to be a stone that promotes stability and balance, as well as a sense of calm and grounding. It is often associated with the earth element and is said to be especially beneficial for those born under the signs of Taurus, Virgo, and Capricorn, which are also earth signs.