Safety Warning from The Philosophers of Nature

Copyright 1998, The Philosophers of Nature. All rights reserved.
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Safety in Practical Alchemy
by Russ House, President, The Philosophers of Nature


This article is being published on the Virtual Alchemical Library to contribute to the safety of those who are drawn to alchemical experimentation. The Philosophers of Nature has granted permission to the Virtual Alchemical Library to republish excerpts from a transcript of one of our practical seminars. The seminar subject matter emphasized laboratory practice of alchemy, and presented much information on one of the possible solutions for creating an animated mercury. We think it necessary to inform readers of these texts of the grave danger in working with metallic mercury, and other metallic compounds without adequate precaution and experience.

The Philosophers of Nature strives to encourage practical experimentation in the Hermetic sciences. In all of our courses, we attempt to identify safety concerns, and to explain their relative risk, so that the individual student can determine whether or not they are presently capable of conducting the experiments that are suggested. Further, we point out, to the extent possible, the means of reducing the risk.

For reasons that should be apparent, it is not possible for our association to present an entire course in laboratory technique and safety that would be meaningful for our students. Such information is easily available on the Internet, and in virtually every used bookstore in the form of academic textbooks for chemistry students.

However, in some cases, the risk of experimentation is such that we develop supplementary papers to alert students to the dangers.

It is imperative that The Philosophers of Nature acts responsibly and takes steps to create an awareness of safety and accountability in the research community. Also, we see it as our responsibility to publish useful research papers that will serve our members today, as well as those who will come after us. This is a delicate balancing act. We consider it necessary to present certain information that will help the student to progressively approach, the Portal of the Temple. On the other hand, some of the experimental work brings with it serious risks. To those who would say that The Philosophers of Nature should not publish this sort of research, I ask this question: "Should we try to stop the distribution of the works of Boyle, Glaser, Newton, the Curies, and Flamel, because of their potential danger?"

Having said this, paths of experimentation using mercury in any form are not suitable for the novice in any case, and are not suitable for even the experienced researcher unless every precaution is taken. Any processes which use metallic mercury or mercury salts (such as chlorides, oxides, sulfides), or ores of mercury are innately dangerous. Further, working with high temperatures to make metallic regulus of antimony exposes the experimenter to risk of severe burns, poisoning from the smoke (primarily antimony oxide particles), and danger of explosion when the nitrates and oxidizable materials are in fusion, or if moisture is accidentally introduced into molten metal.

Please do not begin working on such a path without contemplation of the risk, and a genuine assessment of your present level of skill. You must use safety equipment such as goggles plus a face shield, flame resistant clothing, heavy leather shoes, and flame resistant gloves when making regulus. You must also make certain that there is abundant ventilation (that is, work outside) and be certain that the furnace is cold and no longer emitting metallic fumes when brought inside. A hot furnace can start a fire. It is necessary to keep an orderly work area so that danger of tripping over equipment is avoided. Be cautious of your placement of chemicals - don’t put a hot spoon into the pan of nitre or mixture for the regulus, for example.

Regarding the distillation of mercury... I can not say enough. The vapors of cold mercury are dangerous; when it is being distilled, it is DEADLY! I have not visited any private laboratory that has the proper level of ventilation and safety equipment to permit distillation of mercury indoors. I beg you not to take this warning lightly.

LAB SAFETY: Mercury - A Dangerous Trickster
By Russ House

The purpose of this paper is to make researchers more aware of the properties of metallic mercury. During our seminars, and in certain of our lessons, mention is made of processes using either mercury or mercury compounds, all of which are toxic. If these materials are misused, particularly over a period of time, they will result in irreversible damage to the health, or in death.

The work with animated mercury brings a significant set of problems, which are beyond the scope of this article. First of all, one is distilling amalgam, which creates the potential for exceedingly dangerous levels of mercury vapor in the air. There are, as a result of this danger, issues related to the structural integrity of the equipment used for distillation, which demands airtight seals that do not fuse at the heat of distillation. The processes of washing amalgams, and recovering silver from the ‘doves of Diana’, are examples of other tasks which will require much ingenuity and forethought to accomplish with even marginal levels of safety.

The Philosophers of Nature does not suggest that you perform these experiments, and does not suggest that you ever put yourself, your family, or your community at risk through the mishandling of toxic or other dangerous materials.

I will state a personal opinion, as well. I believe that each of us is working toward our own realization and ultimate freedom, and that each of us must bear the final responsibility for our own actions and choices. It is part of the mission of The Philosophers of Nature to publish information responsibly - it is your responsibility to apply this information appropriately and in safety.

Mercury in Nature

Mercury is an absolutely fascinating metal, which was known to the ancient Chinese and Hindus, and which has been the subject of much interest by alchemists in the both the East and West. Metallic mercury has been found in an Egyptian tomb dating back to 1500 BC. The chief ore is cinnabar (HgS). Today, mercury is extracted from the red mineral cinnabar by roasting the ore in air. Mercury vapor is evolved and then condensed to give the familiar dense, silvery, liquid. Spain and Italy produce about 50% of the world's supply of the metal. Mercury forms alloys called amalgams with most metals, but not iron, nickel or platinum. While mercury occasionally occurs as the native metal in small globules, it more frequently occurs as a crystalline silver amalgam. The word amalgam comes from the Greek, meaning to soften. Mercury literally dissolves other metals and forms an alloy. While most alloys require heat to allow metals to melt and to mix, this is not so with mercury, which will combine with gold, silver, and other metals at room temperature.

Hazard Alert

Mercury is highly toxic by inhalation (0.05 mg per cubic meter of air) and skin absorption (1 mg per 10 cubic meters). Ceiling values should not be exceeded. The most dangerous forms are as a vapor or in a finely divided state (as caused by a spill or splash).

The effects of mercury exposure have long been recognized as hazardous. In Austria, where cinnabar was mined extensively, miner exposure was recognized as a hazard and the number of days per month that miners could work in the mines was limited. This information was recorded as early as the mid 1600’s. The United States government recognized mercury and its compounds as an industrial hazard in the 1800’s. A mercury compound was then used in making felt hats, and hat making was recognized to be a hazardous occupation. The saying, "mad as a hatter" came into being because chronic exposure to mercury and its compounds leads to emotional instability.

Dispensing and Storage

Mercury should be transferred from one vessel to another over a plastic tray to assure that possible spillage can easily be collected. The metal should be dispensed under a fume hood or, failing that, in a well-ventilated area. Always store mercury in a very heavy duty (heavy walled), seamless, glass or plastic bottle, with tight fitting cap. When mercury must be kept in an open container for any amount of time, laboratory workers will place a shallow layer of water over the top of the metal to inhibit evaporation. Since most researchers only use mercury infrequently, it is possible to store the metal in a heavy-duty bottle placed inside a heavy plastic bag. The bagged bottle is stored in a metal can, the bottle being cushioned with vermiculite. If, then, the container of mercury is involved in fire, or otherwise disturbed, this outer can will act as another barrier to prevent breakage and mercury involvement.

The Effects of Mercury

The most dangerous forms of mercury are as a vapor, or in a finely divided state where the maximum surface area of the mercury is exposed. A mercury spill permits hundreds or thousands of minute droplets of mercury to vaporize and contaminate the air. Mercury can generate enough vapor at room temperature to have a very undesirable effect on anyone exposed to the vapor over a period of time. It is important to understand that mercury exposure is a function of the amount of mercury vapor present and, the duration of the exposure. Elevated concentrations of mercury vapor are possible because the vapor pressure of mercury is relatively low. Even at room temperature, the concentration of mercury vapor may be as much as 200 times the threshold limit value (TLV) established by the American Conference of Governmental Industrial Hygienists (ACGIH).

Mercury is a virulent poison, readily absorbed through the respiratory tract, the gastrointestinal tract, or through unbroken skin. Sir Kenelm Digby, a British alchemist, (1603-1665), reported that, "Mercury is so piercing that if you put it on your great toe and then take a ducat (gold coin) in your mouth, the ducat will get a whitish surface."

It is only relatively recently that mercury and its compounds have received publicity as toxic compounds, particularly as environmental pollutants. Mercury has never received the amount of negative publicity, as have other toxic metals such as lead and arsenic. Mercury compounds are retained by tissues and are only slowly eliminated. In 1950, almost 1,000 people were affected by consuming fish from Minamata Bay in Japan. Catalysts containing mercury compounds were used by a local facility to produce plastics, their waste products were being dumped into the bay. The fish in the bay concentrated the contaminant within their tissues until the levels far exceeded those considered hazardous to human health. The symptoms of mercurial poisoning may range from mild gastritis to severe pain with vomiting, and death. Like arsenic and digitalis, mercury is a cumulative toxin, and once it has been absorbed by organic tissue it is difficult to eradicate. It causes damage to the brain and nervous system, causes over stimulation of the glandular system, with resulting overproduction of hormones. It also causes the immune system to be suppressed.

Avoiding Cumulative Exposure

If you work with mercury to any extent, I would highly recommend obtaining a respirator, which is specifically made for mercury vapor protection. Such can be obtained from a source listed at the end of the article for around $100.00 to $140.00. It is important to make certain that the respirator is worn properly to assure protection.

It is unlikely that a single broken thermometer will expose the researcher to life-threatening levels of mercury. Like other heavy metals, however, the effects of mercury are cumulative, since only small amounts of the element can be eliminated at a time by the human organism. For example, numerous thermometers broken and improperly cleaned up over the years could permit accumulation of dangerous levels of the toxic metal in the tissues of the body. Given this danger, every reasonable effort should be made to reduce exposure to mercury. This strategy is the best personal protection for the researcher. One may choose to eliminate the use of mercury thermometers except when a very high degree of accuracy is necessary. Non-mercury thermometers are not as accurate as mercurial thermometers, however, the latter present no mercury hazard. Any mercury thermometer that drops to the floor and breaks will spread mercury in its most dangerous, finely divided form. Any foot traffic then grinds the mercury into even finer particles, exposing more metal and releasing more mercury vapor. This raises the concentrations to more dangerous levels.

Challenges in Cleanup

Mercury is nearly 14 times denser than water, and has a high surface tension. However, mercury has such a low viscosity that it will scatter in every direction when spilled, the droplets rolling and bouncing and breaking into dozens of even tinier droplets. Many of these droplets will not be visible to the human eye. The seams between floor tiles or the crevices that are present in any floor covering provide hiding places for these invisible mercury droplets. Surfaces that are apparently free of mercury will harbor microscopic droplets. Vibrations increase vaporization. Smoking in contaminated areas is very hazardous: tamping a cigarette causes mercury to adhere to the tobacco, and when the cigarette is inhaled, the mercury intake is increased. As the mercury is exposed to air, a skin will form over time, which is an oxide of mercury. The tiny droplets are also easily covered with layers of dust, complicating the clean-up process. Dirty mercury does not easily amalgamate with other metals that one may want to use as part of the clean-up process.

First Steps in Cleanup

In the event of a spill, or if a thermometer is broken, several things should be done at once:

  • Stop all foot traffic in the vicinity of the spill.
  • Stop further activity in lab until cleanup is complete.
  • While in the area, place plastic bags over the shoes to protect them from contamination.
  • Immediately ventilate the area to provide the highest level of air circulation possible. (Air dilution is part of the solution to a mercury spill).

Second Steps in Cleanup

If a large quantity of mercury has been spilled and there are a lot of visible droplets, then mechanical steps are necessary to collect these. Begin by pushing the droplets together to form pools. This must be done without skin contact, and without stirring up dust. The devices then used to pick up the droplets of mercury would best be something like the device shown in the diagram. The water affords a barrier to reduce evaporation of the mercury. If this is not available, a pipette or a glass tube with a finely drawn tip and a vacuum bulb at the other end might be used to pick up each droplet by applying suction, and then release the droplet into a collection bottle. Certainly this is a long and tedious process, but it offers the best means of collecting the visible droplets of mercury. I have had the displeasure of cleaning up such a spill from the crevice-laden floor of my lab, the cleanup taking just under two hours. It is important to be careful in the cleanup process, since mercury is quite heavy, and will not stay in the pipette as well as water.

Before beginning a mercury clean up, it is necessary to remove all jewelry (rings, watches or bracelets) which could possibly come in contact with the spilled mercury. This preliminary stage does not collect all of the mercury, particularly the invisible droplets hidden in the crevices. The purpose of this first step is to collect the largest, most visible droplets, while avoiding the spreading of dust in the area of the spill since the dust will limit the success of the following steps.

Third Steps in Cleanup

The next step in the collection process is to form an amalgam with the mercury that remains in the crevices of the benchtop or the laboratory floor. Zinc metal dust is recommended to form an amalgam with the mercury. The mercury droplets exposed to zinc will form an amalgam that can be swept up and more readily discarded. The use of the flowers of sulfur has been reported to be almost totally ineffective in combining with the mercury. If, however, there are those who have had good results using sulfur, we would like to hear from them. General experience has been to classify the use of sulfur as ineffective.

Devices such as the commercially available mercury collection sponges are effective because zinc metal is woven into the sponge, permitting the mercury to amalgamate with the zinc. One begins this step by sprinkling zinc metal powder extensively in the area where the spill occurred. It is said that zinc metal powder works more effectively in the presence of dilute acetic acid. You may dampen (but not wet) the zinc metal powder with 1/10 normal solution of acetic acid. The zinc dust will expand and make an unpleasant odor. This mixture must not be made up ahead of time and stored, as containers of wet zinc metal powder have been known to explode. It may help to work the zinc into the cracks or pores of the contaminated surface with a broom or brush, if this can be done without risk of dirtying the zinc and the mercury. Dirty mercury simply won’t amalgamate. Wait at least 24 hours for this zinc metal dust to form an amalgam, or at least wait until the zinc metal powder is dry. Then, carefully sweep up this material.

If there are many crevices and cracks in the floor which trapped small droplets of mercury that cannot be picked up by the suction device, and which were not entirely recovered by making an amalgam, one may wish to seal over the cracks with a thick covering of floor wax or an aerosol hair spray. The resulting covering will dramatically reduce vaporization.

Evaluation of Cleanup

Even this process will not get rid of all of the mercury. To see if the levels are now within accepted safety guidelines, one can purchase a hazardous vapor sniffer. To use these, the tiny ends are broken from a detection tube containing specialized indicator chemicals, and a quantitative amount of air from the room environment is drawn through the tube using a calibrated hand pump. The tube is calibrated so that the amount of color developed, is a quantitative indicator of the amount of mercury vapor present. The measurement is both qualitative (color change) and quantitative (length of color change).

Other Concerns

A vacuum cleaner should never be used to clean up a mercury spill! Mercury will have a corrosive effect upon metallic components of the vacuum cleaner, but more significantly, the vacuum cleaner literally creates a mercury aerosol which pumps the mercury vapors right back into the room you’re trying to clean up. Mercury’s most dangerous form to human health is as a vapor or in finely divided droplets. There are special vacuum cleaners made specifically for the purpose of handling mercury. These closed system devices include a trap, which collects the mercury and prevents it from re-entering the environment. Special filters are an integral part of such a mercury vacuum and are routinely changed after a specified level of mercury exposure. These vacuums are very expensive and are out of reach for most individuals.

Broken mercury thermometers in an oven can flood the lab with dangerous mercury vapor. If a mercury thermometer is broken in a heating device, immediately throw open all windows and provide maximum air ventilation. Even if no mercury is visible in the appliance, the appliance should be transported to a hood or out of doors and operated at full temperature to drive off any residual mercury.

Mercury metal cannot be, and should not be disposed of in a landfill, or by placing the metal down a drain. You may wish to consult your local industrial yellow pages to find a firm that accepts the return of mercury for reprocessing.


Chemophobia is the fear of chemicals. Our intent in this article is to provide more knowledge about mercury - the sort of knowledge that can destroy fear. When used under responsible conditions and controlled by a responsible and well-informed researcher, mercury can be an important part of laboratory research. One can not render mercury safe to work with, but one can create an environment and a sense of caution and responsibility, which will reduce risk.

Source for Safety Equipment: Lab Safety Supply, +1 (800) 356-0722. Has extensive catalog of lab and industrial safety equipment, with respirators, mercury spill kits, mercury monitors, and associated equipment.


  • Flinn Fax safety notice, 1987 by Flinn Scientific, Batavia, IL.
  • Chemical Technicians’ Ready Reference Handbook, G. Shugar, R. Shugar, L. Bauman, R. Bauman, McGraw-Hill Book Co., 1981.
  • Handbook of Chemistry and Physics, 65th Edition, CRC Press, 1985.
  • Encouragement and reminders from researchers associated with The Philosophers of Nature.
  • The grim reminder of the occasional accident.

Copyright 1998, The Philosophers of Nature. All rights reserved.
Contact The Philosophers of Nature for further information on practical alchemy.
Email: Web Page: