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Robert Simmons has given the name "Merkabite" to this Calcite because it is believed to awaken and activate the "Merkabah vehicle of Light" also known as the "Rainbow Body". It is said to powerfully open the third eye and crown chakras and to help one receive energies from the higher planes.
I would add though to be realistic with this information as the Merkabah body of light is an extremely sacred experience built over many meditations. A stone itself will not bring about a Merkabah experience, but as an approach to the subject this stone is a step in the right direction.