Star Tetrahedron inside Star Tetrahedron 28mm

Due to the popularity of Drunvalo Melchizedek's 'Flower of Life Worshops' and books, the  star tetrahedron is nowadays often refered to as 'the Merkabah', (vehicle  of chariot for the light body of the soul to travel the planes of existence in).  

 The star tetrahedron is also called the 'stella octangula' because of its 8 vertices.  A tetrahedron by itself is polarised, whereas two interpenetrating like this is a union of the polarities. 

This form is also part of whay Buckminster Fuller called the 'isotropic vector matrix', the triangular hexagonal  grid formed by packing spheres as closely as possible.