Traditionally, a pentagram - or five-point star - is a symbol having mystical associations with the number 5, especially as 5 relates to humans: For example, there are five fingers on each hand, five toes on each foot, and five senses.
When a pentagram is enclosed by a circle it is regarded as a 'pentacle', which has further meaning.
Wiccans, for example, see the circle as protecting the pentagram and everything it symbolizes. Therefore they use the pentacle as a ritual tool because of its powers to protect. And the enclosing circle itself also has meaning, such as: the earth, the cyclic nature of life, infinity, and harmony.
All these meanings come together in this slightly occult-looking necklace. The upright five-pointed pentagram is enclosed by a circle that is formed by the trunk, branches, and roots of a very woody tree of life.
The overall design is very naturalistic with an element of drama; partly because of the asymmetric arrangement with the pentagram set off to one side, and also because of the snarl of twisting branches and roots.
The pendant is dome-shaped, which adds another dimension to the patterns of light reflecting off the many surfaces of the branches and roots.