Diamond is a stone that is used to bring energies of longevity, balance, clarity, intensity, success, and abundance. It also brings eternity, purity, and high frequency energy. It also is a stone of amplification, including thoughts, strengths, and weaknesses.
Diamonds are said by some to be the best for metaphysical use. They are high vibration stones that radiate Light energy and bring Light consciousness. They increase energy in all endeavors and link to Divine energy. It is one stone that can connect to spiritual realms.
With the connection to spiritual realms, they are even said to help move one along through soul evolution. They can help align with Higher Mind and connect to one's personal path.