Pyramid

The pyramid is called a Tetrahedron in Sacred Geometry, and its main function is assisting with manifestation. This shape is the contrasting yet harmonious output of energy that is at work within the shape. The solid structure base, much like a cube, has a very grounded and stabilized energy, while still allowing energy to directly flow out of the point. Pyramids connect energy from the crown chakra to the root chakra, allowing us to feel in tune with higher dimensional thinking/our higher selves while still staying grounded to Earth.

https://rockswithsass.com/blogs/news/crystal-shapes-their-meaning-and-uses