Quintessence

From Latin quinta, quintus "fifth" + essentia (essence) "being, essence," abstract noun formed in imitation of Greek ousia "being, essence," from ontos, einai "to be", from essent-, esse "to be". Quintessence, "the fifth element," is a symbolic name in Alchemy for the substance the four elements come from, and through purification and perfection can return to, but elevated. This substance is also known as Ether or Akash, and when purified, Kundalini.

“The Magi in their wisdom asserted that all creatures might be brought to one unified substance, which substance they affirm may, by purifications and purgations, attain to so high a degree of subtlety, such divine nature and occult property, as to work wonderful results. For they considered that by returning to the earth, and by a supreme magical separation, a certain perfect substance would come forth, which is at length, by many industrious and prolonged preparations, exalted and raised up above the range of vegetable substances into mineral, above mineral into metallic, and above perfect metallic substances into a perpetual and divine Quintessence, including in itself the essence of all celestial and terrestrial creatures.” - Paracelsus, The Aurora of the Philosophers

"Q. Where does the metallic nature store her seeds? A. In the four elements. Q. With what materials can the philosopher alone accomplish anything? A. With the germ of the given matter; this is its elixir or quintessence, more precious by far, and more useful, to the artist, than is Nature herself. Before the philosopher has extracted the seed, or germ, Nature, in his behalf, will be ready to perform her duty. Q. What is the germ, or seed, of any substance? A. It is the most subtle and perfect decoction and digestion of the substance itself; or, rather, it is the Balm of Sulphur, which is identical with the Radical Moisture of Metals. Q. By what is this seed, or germ, engendered? A. By the four elements, subject to the will of the Supreme Being, and through the direct intervention of the imagination of Nature." - Paracelsus, Alchemical Catechism

“ÆTHER, in esotericism, is the very quintessence of all possible energy, and it is certainly to this universal agent (composed of many agents) that all the manifestations of energy in the material, psychic and spiritual worlds are due.” - Blavatsky, The Secret Doctrine

"...Isis, or Nature, the first matter (alchemical terminology), [is] the essence of the four elements (life, light, heat, and force), which quintessence generated all things." - Blavatsky, The Secret Doctrine

"We need to refine ourselves, to become quintessential, to truly purify ourselves, if truly what we long for is to seriously experience the tremendous realities contained in the divine Christic symbolism." - Samael Aun Weor, The Three Mountains