852 Hz is the highest of the six core Solfeggio frequencies, and in the sound-healing literature it is the tone associated with the brow or third-eye centre and with "returning to spiritual order", awakening and the intuitive and spiritual faculties. It completes the original ascending set below the later-added 963 Hz. Like the whole scheme it is a modern construction: the core six were assembled by Joseph Puleo and popularised from 1999 by a numerological reading of a Latin hymn and a biblical passage, not drawn from any documented historical tradition, and the borrowed solfege name has no genuine tie to the medieval scale, which knew no fixed pitch in hertz.
The frequencies are now a staple of streamed and recorded relaxation and "sound-healing" music. There is no scientific evidence that 852 Hz produces the claimed spiritual or perceptual effects, and nothing here is offered as medical advice, diagnosis or treatment; the account describes the beliefs attached to the tone within a modern esoteric and commercial tradition.
Sources Healing Codes for the Biological ApocalypseLeonard G. Horowitz and Joseph S. Puleo with Claiming Knowledge: Strategies of Epistemology from Theosophy to the New AgeOlav Hammer