These are high quality cut and polished Clear Quartz Obelisks from Brazil. An obelisk is a standing crystal that is pointed and tapered at one end. Energy is directed through and radiates from the point of the crystal.
Obelisks have been strategically placed on the earth to slowly dissipate any energy build up that could cause destruction. The shape maintains the balance of earth energy by taking the stored energies and releasing them into the atomosphere to be circulated around the globe.
Crystal obelisks act in the same manner when they are placed in a building. If there is a build up of energies, the obelisk can dissipate the build up. Crystal obelisks are also storehouses of knowledge.