Black tourmaline is one of the best negative energy sucker stones there are. It helps with negative energy in a space as well as on a person. it is said to cleanse, purify, and transform negative energy into a higher vibration. It balances the chakras and help energetically protect an individuals energy field.
What makes these interesting is Povondraite )a rare variant of Tourmaline) are rare because it has distorted prism growths within the typical tourmaline triangular growth structure. It has other elements such as chromium, that were introduced during the early stages of growth, making it a really interesting metaphysical stone. Chromium helps one to find joy, and helps the process of transmuting negative energy in more aspects than one.
Unlike traditional tourmaline, it doesn't seem to need to be energetically cleansed.
(Used to be called Ferridravite, but upon further research they are different compositions of stones.)