For those interested in such things, i post here some info about Neidan and Daoist alchemy in general. It is all based on a book i found, i post a link here:
https://mega.nz/file/BHATEbTI#HTQfgygUmxlvAgSb9cZLJmkDX1o05fUq8kEZOP609aIThe book is not big, but i decided to summarize it even more and break it into basic concepts. Here we go:
DAOIST ALCHEMY - BASE CONCEPTSThe main goal of the practitioner of Daoist alchemy (both internal and external) is to heal, purify and transform his body, energy and spirit to reach the original state of Dao. Those who had acheved this can reach transcendense and immortality, longevity and health, communicate with deities of the celestial pantheon and gain protection from spirits, demons and other evil entities.
External Alchemy (Waidan) - Focuses on mixing and transmuting the natural elements to create alchemical gold and various potions and elixirs.
Internal Alchemy (Neidan) - Seeks to produce elixirs directly inside the body, by using one's own energies and reaching their inner gods through physical and meditative techniques.
Alchemist (Fangshi) - "Fangshi" is translated as "alchemist", "recipe master" or "method master" and describe practitioners of various schools in Daoism, including Neidan and Waidan, but not limited only to these two.
Talismans (Fu) - Used to purify and protect the Waidan master and the ritual place from harmful influences, creating a spiritual barrier that only he and his disciples can enter.
Invocation - A part of Waidan ritual. The alchemist invokes the 3 main Daoist deities: Da Daojun (Lord of the Dao), Laojun (Lord Lao - deified Laozi) and Taihe jun (Lord of Great Harmony), before mixing the components in a tightly closed crucible and transmuting them by fire.
Alchemical Compounds - Used in Waidan transmutation recipes. The most common ones are cinnabar, lead, mercury, realgar, orpiment, malachite, magnetite, and arsenolite.
Alchemical Conjoinment - in both teachings: unification of Yin and Yang (either in the form of external alchemical elements or internal energies in the body) which brings back the original cosmic state, creating The Golden Elixir of Immortality.
Inner Gods - In Neidan tradition, the human being is a host to a pantheon of gods, representing the formless Dao or main cosmic principles such as Yin and Yang or the five elements. The inner gods enable the human being to communicate with the corresponding gods of the celestial pantheon, serve as administrators of the body, and preside over its balance.
Red Child (Chizi) - The most important of the inner gods. It resides in the stomach and, like the Supreme Ruler of Heaven, it is a transformation of the Breath of Dao. The Red Child represents one’s “true self” (zhenwu).
Yellow Essense (huangjing) - In Neidan it represents the Moon (Yin) energy, circulating in the human body. Used as an offering to the Inner gods, along with the Red Breath (see below).
Red Breath (chiqi) - In Neidan represents the Sun (Yang) energy, circulating in the human body. Used as an offering to the Inner gods, along with the Yellow Essense.
Alchemical Juices - Substances produced in the body of a Neidan prectitioner, used to nourish the inner gods and awaken the organs in which they reside. Their names are Jade Liquor (yuye), Golden Nectar (jinli) and Golden Liquor (jinye).
Nine Elixirs (jiudan) - called also “breaths of the Nine Heavens”, these are nine meditative states that a Neidan practitioner goes through in his search for immortality before reaching the ultimate state of the original Emptiness.
Eight Trigrams (bagua) - the eight trigrams symbolize basic things and phenomena of nature or society. The ancient Chinese use the interchanges and transformations of the eight trigrams and what they represented to understand and expound on natural and social changes and to explain why and how they took place. Each of the eight trigrams consists of three lines and each line is either divided (- -) or undivided (—), representing yin or yang respectively, and most important are the first four. The eight trigrams are:
qian (☰) - heaven
kun (☷) - earth
kan (☵) - water
li (☲) - fire
zhen (☳) - thunder
xun (☴) - wind
dui (☱) - lake
gen (☶) - mountain
Five Agents (wuxing) - They are Wood, Fire, Soil, Metal, and Water. The five agents are generated by the division of Unity into Yin and Yang, and by the further subdivision of Yin and Yang into four states. Water and Wood are cosidered Yin, Fire and Metal are Yang; Soil has both and serves as an unifier of all the others.
Three Treasures (sanbao) - The Three Treasures are the basic elements of the cosmos and the human being. They are: Essense (jing), Breath (qi), and Spirit (shen). Shen, qi, and jing (in this order) represent, in their precosmic aspects, three stages in the process of self-manifestation of the Dao, from the state of Emptiness to the coagulation of the Essence that generates the cosmos. Neidan seeks to revert this process by transmuting back Essence to Breath, Breath to Spirit, and Spirit to Emptiness - the immortal state of being.
Cinnabar Fields (dantian) - These are the centerpoints of the Three Treasures in the human body. They play a major role in Taoist breathing, meditation, and Neidan practices.
The Lower Cinnabar Field, located in the abdomen, is the seat of Essence (jing) and is where the Inner Elixir is originally created.
The Middle Cinnabar Field is at the center of the chest ans is the seat of Breath (qi). In the second stage of the Neidan process (Essence to Breath), the Elixir is moved to the Middle Field and is nourished there.
The Upper Cinnabar Field is located in the region of the brain and is the seat of Spirit (shen). Moving the Elixir to the Upper Field marks the third and final stage of the Neidan process.
Fire Phases (huohou) - The Fire Phases are multiple cycles trough which the Neidan practitioner goes in the process of circulating and transmuting his Essense. They constitute one of the most secret parts of the alchemical work, and that the masters adapt them to the qualifications and the needs of their disciples.
