Dendritic Agate is not banded and so is not strictly an Agate in scientific terms. It gets its name from a Greek word meaning tree-like, and this is quite descriptive of these stones. They are usually colorless, white or gray (though some are a lovely light purple), with tree-like or fern-like inclusions of iron or manganese. The inclusions are called dendrites.
Dendritic Agates are ideal tools for strengthening the fiber of the self through inner work.
Those involved in therapy, meditation practice, rebirthing, a twelve-step program or any other path of serious inner work will find Dendritic Agate to be a helpful talisman. Carrying or wearing one of these stones or keeping it on one’s altar will assist one in taking the day-by-day steps that are necessary to achieve the desired insights and behavior changes. Dendritic Agate helps one to keep a positive, though not unrealistic, attitude while going through needed transformations. It also assists in keeping one in touch with the physical world, so one does not live merely in one’s thoughts and mental processes.
These stones can help reduce stress in difficult times, promoting a good-natured acceptance of one’s circumstances, as well as offering long-term help in improving them. The purple varieties of Dendritic Agate are particularly well suited to purification of the body and energy field, and to working towards spiritual transformation.
Simmons, Robert; Ahsian, Naisha. The Book of Stones, Revised Edition: Who They Are and What They Teach (several pages). North Atlantic Books. Kindle Edition.