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Sylvia Rose

Mercury II Oxide: Red & White of Alchemy

In practical alchemy, mercury II oxide (HgO) is often called the "Red Precipitate," with its compound Mercuric Amidochloride (Hg(NH2)Cl), known as the "White Precipitate." Red and White appear often in alchemy and become highly spiritualized by the Renaissance.



red and white alchemy potions

The Red and White in Spiritual Terms



The Red and the White in alchemy can refer to the alchemical marriage or conjunction and the steps required to reach this. In practical alchemy the red and white are metals, chemical reactions and processes, even pigments, as the early alchemist knows how to make colors.


In practical alchemy, the red precipitate and white precipitate are the sediments settling at the bottom of the vessel. An example of precipitation is shown in the handy pic below.



precipitate in science
A blue precipitate

As alchemy becomes more spiritualized, largely through Eastern influence and the rise of mysticism in the medieval period, the red and white evolve into symbols and figures like the Red King (sun, sulfur, male principle) and White Queen (moon, mercury, female principle).


The amazing artwork of Splendor Solis dramatizes the symbols of alchemy in glorious color. Splendor Solis is an alchemical treatise originating from a manuscript edition dating back to around 1582.


The manuscript is 100 pages of German text with 22 elaborate allegorical illuminations. The images are rich in symbolism, the meanings a mystery. To true believers, they represent secret alchemy methods, related to the production of the theoretical philosopher's stone.



White Queen and Red King, Splendor Solis 1582
White Queen and Red King, Splendor Solis 1582

In the 16th century people like Michael Maier create major works based on the union of the Red (Solar) king and White (Lunar) queen. Their conjunction gives birth to a miracle: the Rebis, Divine Hermaphrodite, exalted symbolic child of Hermes and Aphrodite.


Michael Maier is a great contributor to the spirituality of alchemy. Until the overthrow of Holy Roman Emperor Rudolf II in 1611-12, Maier spends time at his court as his personal physician. Rudolf bestows knighthood upon him almost immediately.


Writer, physician and alchemist, Maier also composes music, included in the pages of his most famous work, Atalanta Fugiens (1617). The beautiful artworks of this compilation are by renowned Swiss engraver Matthäus Merian the Elder.

   


Seeking the Philosophers' Stone, by Matthäus Merian for Michael Maier's Atalanta Fugiens
Seeking the Philosophers' Stone, by Matthäus Merian for Michael Maier's Atalanta Fugiens

Red and white appear in references throughout the 2000-year-old history of alchemy, some associated with daily life. For instance, the tartar salts of alchemy are crystals of white and red wine, or wine diamonds. In medieval times, red and white lead are favored in art.


Red, white and black are the first three colors an infant sees. The 900 AD Turba of Philosophers admonishes practitioners to "redden the white and whiten the red," further stating there can be no red without first the white.



Turba Philosophorum
Turba Philosophorum

In practical alchemy the union of red and white is generally the conjunction of sulfur and mercury. Red and white are two of the four processes of Maria when she explains phases of copper treatment.


Red and white are colors of candy canes, invented in Cologne, Germany, to keep children quiet during Christmas Eve Mass. Spirituality in alchemy is strongly associated with religion due to the spread of Christianity. It's also connected to Hermeticism.



hermetic symbols
Hermetic Symbols

Above: Symbols of Hermeticism: Dragon representing earthly matters and alchemical transcendence; the Emerald Tablet; Ibis representing the Egyptian god Thoth; the caduceus of Hermes / Mercury; small canine refers to Sirius, the Dog Star.


The red and white arise in metallurgy, dyes, alchemistry, pigment making, spiritual awakening, or a colorful chemical reaction of white and red socks when washed together, also called "the pinkening." Chlorine bleach (NaClO) can re-whiten pinks obtained this way.


Scientific Process - Red and White



The Red: Mercury II Oxide (HgO)


The preparation of mercury II oxide can be traced back to the 11th-century Arabic-Spanish alchemist Maslama al-Majriti. His work pioneers many alchemical processes and significantly contributes to the understanding of mercury’s compounds.



red and yellow
The Red - Red and Yellow manifestations of HgO

HgO is historically known as the "Red Precipitate". It's pivotal in science and other fields. Its striking color and diverse applications attract attention for centuries. HgO can appear as a red crystalline powder or as yellow powder, with the red variety being the most famous.


Preparation of Mercury II Oxide


Mercury II Oxide can be synthesized through the thermal decomposition of mercuric nitrate or by heating mercury with oxygen or air:


  1. Thermal Decomposition: When mercuric nitrate ((Hg(NO_3)_2)) is heated, it decomposes to give HgO along with nitrogen dioxide and oxygen gases.

  2. Direct Oxidation: Mercury metal can be oxidized by directly heating it in the presence of oxygen.


Traditionally, HgO is produced through the thermal decomposition of mercury (II) nitrate by heating it in the presence of oxygen. For example, heating 1 mole of mercury (II) nitrate can yield approximately 0.63 moles of HgO as well as nitrogen dioxide and oxygen gas.



Mercury / Quicksilver Hg
Mercury / Quicksilver Hg

Occurrence in Nature


In nature, mercury II oxide is rare in pure form. It's a product of the oxidation of elemental mercury under specific conditions. Most mercury occurs in natural deposits as minerals, typically in sulfide forms like cinnabar.


Toxicity of Mercury II Oxide


Mercury II oxide is well known for its toxic properties. Exposure can lead to mercury poisoning, which affects the nervous system, kidneys, and immune system. Due to its potential health hazards, proper safety measures must be followed if one is to survive unscathed.



guy in hazmat suit with chemicals

As a mercury compound, it's dangerous to human health and the environment. Symptoms of mercury poisoning include:


  • insomnia

  • headaches

  • tremors, shakes

  • confusion

  • memory loss

  • other cognitive dysfunction

  • spasms and convulsions

  • madness

  • death


Even small amounts can be toxic, with ingestion or inhalation presenting significant health risks. This is why ancient Romans send only convicts or unmanageable slaves to work the horrendous Almadén mercury mines.



medieval cinnabar (mercury) distillation apparatus
medieval cinnabar (mercury) distillation apparatus

Uses of Mercury II Oxide


Historically, mercury II oxide has uses such as:


  • Pigment in paints due to intense red coloration. In ceramics and glassware it's also used as a red pigment, giving pottery and glazed items a vivid color.

  • Production of other mercury compounds and as a catalyst in chemical reactions.

  • In ancient medicine, with caution due to known toxicity. People are not always cautious, as one of the popular treatments for syphilis in medieval times is to rub oneself all over with pure mercury. Syphilis in the Middle Ages causes breakouts and rashes in skin-peeling afflictions and oozing sores all over the body.



Treatment of Syphilis with guayabo wood
Treatment of Syphilis with guayabo (guava) wood

The White: Mercuric Amidochloride (Hg(NH2)Cl)


In contrast to its red counterpart, mercuric amidochloride is recognized for its white crystalline form. Mercuric amidochloride is often associated with mercury II chloride (HgCl2), as they share some chemical properties and synthesis methods.


Presence of amine groups in mercuric amidochloride gives it distinct characteristics and applications. Mercuric amidochloride is intrinsically linked to mercury II chloride as its derivative.


This compound forms when ammonia reacts with mercuric chloride, where the amine groups successfully replace the chloride ions. This reaction is pivotal in synthetic applications.



Mercuric Amidochloride
Mercuric Amidochloride - the White

Discovery of Mercuric Amidochloride


Early chemists discover mercuric amidochloride while exploring reactions of mercury and amines. Although the specific timeline is less documented than that of HgO, it has been recognized as a compound since the 19th century.


The discovery of mercuric amidochloride dates back to the late 17th century. Al-chemists observe mercury's ability to react with ammonia, forming this white precipitate. The discovery gives further understanding of mercury's chemical behavior.



toxic chemicals mercury
toxic chemicals - mercury

Preparation of Mercuric Amidochloride


Mercuric Amidochloride is predominantly prepared by reacting mercuric chloride with ammonia or an amine in an aqueous solution. This leads to the formation of a white precipitate, which is characteristic of the compound:

  1. Reaction: The reaction can be represented as: [ HgCl_2 + 2NH_3 --> Hg(NH_2)Cl + NH_4Cl ]


Synthesis occurs by mixing mercuric chloride with ammonia solutions. The reaction generates a white precipitate that, once filtered and dried, yields the final product. This simple method remains prevalent in labs today.


Uses of Mercuric Amidochloride


  • Medical Disinfectant: Sometimes used in disinfectant formulations, although its use has declined due to safety concerns.

  • Chemical Synthesis: A key player in organic synthesis and reagent production.

  • Textile Industry: Previously used as a mordant to enhance dye adherence in fabrics.


Like mercury II oxide, mercuric amidochloride is highly toxic.



Traditional (non-toxic) dyeing of yellow weld, a popular medieval color. A mordant is used to keep the colors fast.
Traditional (non-toxic) dyeing of yellow weld, a popular medieval color. A mordant is used to keep the colors fast.

Non-Fiction Books:


Fiction Books:

READ: Lora Ley Adventures - Germanic Mythology Fiction Series

READ: Reiker For Hire - Victorian Detective Murder Mysteries





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