Mummifying an animal is a straightforward preservation process that relies on one core principle: removing moisture faster than bacteria can break down tissue. Salt-based mixtures draw water out of cells through osmotic pressure, creating an environment where microbes can’t survive. The technique works on specimens of any size, from insects to small mammals, though smaller animals are far more practical for a first attempt.
What You Need
The key material is a desiccant, a substance that aggressively absorbs moisture. Ancient Egyptians used natron, a naturally occurring mineral salt. You can make a close equivalent by mixing equal parts baking soda and table salt by weight. Some people combine the dry ingredients with a small amount of water to form a paste, let the two compounds bind together, then bake the mixture in an oven until it’s completely dry again. This fused powder works more effectively than simply stirring the two ingredients together.
Beyond the desiccant, gather the following:
- A lidded plastic container large enough to hold the specimen with several inches of clearance on all sides
- Rubbing alcohol (70% isopropyl) for initial disinfection
- Cotton batting or stuffing for filling body cavities
- Gauze or thin fabric strips if you plan to wrap the finished specimen
- A kitchen scale for tracking weight loss over time
For safety, use waterproof gloves and protective eyewear whenever handling the specimen. Dead animals can carry pathogens like Salmonella and E. coli. Wash your hands thoroughly after every session, clean work clothes separately from everyday laundry, and work in a well-ventilated area. If the specimen produces a strong rotten-egg smell at any point, that’s hydrogen sulfide, and you should move away and ventilate the space immediately.
Choosing a Specimen
Small animals produce the best results for beginners. Fish, frogs, lizards, mice, and small birds are all good candidates. The smaller the animal, the faster moisture escapes the tissue and the lower the risk of internal decay outpacing the desiccation process. A mouse or similarly sized creature can mummify fully in a matter of weeks, while larger specimens take months or longer.
Use an animal that died of natural causes or was found already dead. Freshness matters. A specimen that’s already begun to decompose will be harder to preserve and more hazardous to handle. If the animal is frozen, thaw it completely before starting.
Removing Organs and Cleaning the Body
Internal organs contain the most moisture and bacteria in the body, so removing them dramatically improves your results. Make a small incision along the abdomen and carefully extract the contents of the chest and abdominal cavities. For very small specimens like mice, a pair of tweezers helps. You don’t need surgical precision here. The goal is simply to remove the bulk of the soft, wet organs.
Once the cavity is empty, rinse the interior with rubbing alcohol to kill surface bacteria. Then pack the cavity firmly with cotton batting. This gives the body structure during drying and provides an internal wick that helps draw moisture outward. If you want to preserve a particular pose, position the limbs now, because once drying begins, the tissue will stiffen in place.
Burying the Specimen in Desiccant
Pour a layer of your natron mixture about two inches deep into the bottom of your container. Place the specimen on top, then completely cover it with more of the mixture. Every surface should have direct contact with the salt blend, with at least an inch of coverage on all sides. For a small bird or mouse, you’ll typically need two to three pounds of the mixture.
Seal the container with its lid and store it somewhere dry and room temperature, away from direct sunlight. A garage shelf, closet, or basement works well. Heat speeds evaporation but can also cause fat to render out of tissue, which creates odor and discoloration, so avoid warm spots.
After the first week, open the container and check the desiccant. If it feels damp or clumpy, replace it entirely with a fresh batch. The first replacement is almost always necessary because the initial moisture loss is rapid. For a mouse-sized specimen, you may need to swap the mixture once or twice. For anything larger, expect three or four changes over the course of the process.
How Long It Takes
Timeline depends entirely on the specimen’s size. Research on natural mummification has documented small carcasses drying completely in under 30 days in favorable conditions. With active desiccation using salt mixtures, a small rodent or lizard typically reaches full preservation in three to six weeks. A small bird may take slightly longer because feathers trap some moisture near the skin.
A long-term study using a full pig carcass (roughly 88 kg starting weight) as a model for Egyptian-style mummification found that the body lost about 30% of its weight in the first 200 days, reached 50% weight loss after about 650 days, and ultimately stabilized at around 35% of its original weight after 13 years. The takeaway: larger specimens require extraordinary patience. For a home project, stick with animals under a pound or two.
Weigh your specimen before you begin and periodically during the process. When the weight stabilizes over two consecutive checks spaced a week apart, drying is essentially complete. The finished specimen should feel rigid, lightweight, and completely dry to the touch, with no soft or pliable areas.
Applying Resin or Protective Coating
Once the specimen is fully dried, brush off all remaining salt mixture with a soft paintbrush. At this stage, the mummy is preserved but still vulnerable to moisture in the air, insects, and physical damage.
Ancient Egyptian priests coated mummies with warm tree resin at multiple stages to seal out moisture and add antimicrobial protection. Frankincense and myrrh resins both have well-documented antibacterial properties, active against common pathogens including Staphylococcus aureus. You can purchase frankincense or myrrh resin, melt it gently in a double boiler, and paint a thin layer over the specimen with a disposable brush. Alternatively, a coat of clear polyurethane or even white glue thinned with water serves a similar sealing function if historical accuracy isn’t your goal.
Wrapping the Mummy
Wrapping is optional but protects the specimen and gives it the classic mummified appearance. Cut thin strips of linen, cotton muslin, or gauze about one to two inches wide. Starting at the extremities, wind strips around each limb individually, then work inward toward the torso. Egyptian priests wrapped each finger and toe separately before covering the whole hand or foot, using hundreds of yards of linen for a human-sized mummy. For a small animal, a few yards of fabric is plenty.
Between layers, brush on a thin coat of resin or diluted white glue. This bonds the layers together and adds another moisture barrier. If you’re using the resin approach, warm resin between wrapping stages is the traditional method. Once the final layer is in place, secure the end of the strip with a small dab of adhesive or tuck it under a previous layer.
Long-Term Storage
A properly mummified specimen stored in dry conditions can last indefinitely. Keep it in a display case or sealed container away from humidity. Silica gel packets placed near the mummy help absorb any ambient moisture. Avoid handling it with bare hands, both because skin oils can degrade the surface over time and because residual preservative salts can irritate your skin.
If you notice any soft spots developing months later, that’s a sign moisture has re-entered the tissue. You can often rescue the specimen by re-burying it in fresh desiccant for another week or two, then resealing the affected area with resin.