From Ethereal Whispering, around 740 BF, Translated from Tulamidya:
To receive a vision of the Adamantine Heart: Choose one of the days of Mathazilel, Azamir or Nishkakat, that your Clarobservantia penetrates spheres. Secondly, return to the vision in the nocturnal hours, so that the sunshine does not bedazzle your gaze. For one, burn a zithabar in a bowl made of the wood of the Travelers' Tree and breathe in the plumes of smoke seven times. Then cut the glyph of the mind into your forehead with a sharp onyx stone, where it joins the root of the nose, and smear the juice of the spotted lotus onto the blood. Listen to the sounds of the Matjanga melody played on the Kabas flute. Wrap both hands around a pure table-cut diamond, and move it from heart to forehead and back again, over and over. If you have done what is described, then you will see the Adamantine Heart, a pearl-white stone, a glowing Triakisdodekaeder, a consummate figure, veiled in the red and green fog of dreams. No matter if trampled by fate, or imprisoned by gods, it doesn't want to be forgotten and send out this vision. Pay attention to the signs, and you may decipher the path to the Heart. Wait for the first heartbeat, and the vision will end.