This is a Celtic Cross Crystal Grid, Made of birch plywood. It is 1/4" thick.
The symbolism of the Celtic cross is indicative of the human desire to know and experience the unfolding mystery of life. The arms of the cross offer four ways to ascension, an invitation to objectively know nature, wisdom, god/goddess, and the self.
Crystal grid and healing sets are groups of stones that go together for a purpose. Sets of crystals and stones are used for ritual magickal or spiritual crystal healing purposes or with Reiki-Seichim energy work for healing. Some are generalized and others have specific purposes.