There are many types of Agates and is a mineral of the quartz family. Blue Lace, Fire and Moss to name a few. Agates have been discovered with artifacts of Neolithic people and used by the early Egyptians and in ancient India in jewelry. Generally known as stones of lower intensity and slower vibrational frequency, this is not considered a defect but considered to be a stabilizing and strengthening influence with whatever energy pattern a particular Agate variety represents.
*Gemstone information gathered from "The Book of Stones" by Robert Simmons and Naisha Ahsian. Pick this book up for an in-depth description of almost every stone on Earth!