A Vastu pyramid is a geometric object that's believed to enhance the energy in a space and correct Vastu doshas. Vastu pyramids are thought to align with the Earth's magnetic field and universal energies. 
How Vastu pyramids are believed to work 
Energy amplification: Pyramids are thought to amplify positive energy and reduce negative energy.
Energy balancing: Pyramids are thought to balance the energy in a space.
Energy clearing: Pyramids are thought to absorb and transmute negative vibrations.
Alignment with cosmic forces: Pyramids are thought to align with the Earth's magnetic field and universal energies.
How to use Vastu pyramids
Place the pyramid in a location where people spend the most time. 
Place the pyramid in the north-east corner of the house. 
Place the pyramid on the floor near the main door. 
Place the pyramid on the study table to improve academic results. 
Place the pyramid on important machines in an industry to reduce maintenance costs and improve production