My strange and wonderful daughter has an obsession with bones since she was three years old. She even asked me if she could have my bones when I die. I said yes, but since we aren’t at that point yet, right now we are gathering all sorts of animal bones and cleaning them. 🙂
Cleaning and whitening animal bones for display is actually fairly simple. Below I’ll get into the details of what to do in each step of the bone cleaning process.
Guess what? I wrote an entire eBook about cleaning bones. It covers a lot more than I could fit in this article, including lots of expert tips and hacks that amateurs can use. You can buy it here (instant PDF download) for $4.99!
Jump to:
- How to Clean and Whiten Bones
- Step 1: Supplies
- Step 2: Removing Soft Tissue
- Step 3: Precleaning the Bones
- Step 4: Degreasing the Bones
- Step 5: Soaking in Hydrogen Peroxide
- Before/After Pictures
- Tips for Very Large Skulls or Bones
- Trash Bag Trick
- Baking Soda + H202 Paste
- Cream Hair Developer
How to Clean and Whiten Bones
Cleaning small bones is pretty easy. However, it may take some time -especially if the animal is fresh and has lots of soft tissue on it still.
Step 1: Supplies
In order to clean animal bones, you will need the following supplies:
- Gloves
- Buckets or trash cans that can hold the bones being cleaned
- Dish soap
- Scrub brushes
- Hydrogen peroxide
Depending on the type of bones and their condition, you might need some other supplies too, such as as a power washer, muslin sack, pliers for removing teeth, and ammonia for degreasing.
Never Use Bleach for Whitening Bones
A lot of articles online about how to whiten bones say to “bleach” the bones. You should NEVER use bleach to get bones white. Why? Bleach will destroy the structural integrity of the bones.
Likewise, you don’t want to use any laundry detergents for cleaning or degreasing the bones. These detergents often contain bleach or other harsh chemicals which can destroy the bone.
Use Hydrogen Peroxide to Whiten Bones
Hydrogen peroxide (H2o2) is the safest and most effective way to whiten bones. This is what taxidermists use, including the ones at the Smithsonian and other prestigious institutions.
You can use the 3% hydrogen peroxide found in drug stores to whiten bones. The problem is that this peroxide is very weak. You’ll either need to buy a zillion bottles of it or do multiple soaks to get the bones clean and white. To get good results, you want 12% hydrogen peroxide.
Hair Developer As an Alternative to Hydrogen Peroxide
Unfortunately, not many pharmacies stock concentrated hydrogen peroxide in that concentration. If you can’t find 12% or higher hydrogen peroxide, you canuse hair developer instead.
There are two types of hair developer:
- Clear Developer: This is the exact same thing as the hydrogen peroxide you’d get in a pharmacy. It will bubble up nicely and works great for cleaning bones.Get 40 volume clear developer here.
- Cream Developer:This has some emulsifiers added so it is creamy and thick. Some hardcore taxidermists won’t use it, saying the emulsifiers could mess up the bones. It also won’t bubble up like clear H202, so it isn’t as good at getting stains out from deep within bones. However, because cream developer is thick, it can be painted directly onto bones for spot whitening or for whitening skulls with antlers.Get 40 volume cream developer here.
Hair Developer Strengths:
Hair developer is listed in strengths by volume. Don’t think that 10v equals 10% though. The actual concentrations are as follows:
- 10 volume =3% hydrogen peroxide.Don’t get this. It’s too weak for good results!
- 20 volume =6% hydrogen peroxide.
- 30 volume =9% hydrogen peroxide.
- 40 volume =12% hydrogen peroxide.
This giant bottle of hair developer (hydrogen peroxide) is 12% and is really affordable for a gallon.Buy it here.
Step 2: Remove soft tissue
If you found a bone that has been sitting in nature for a long time, then it won’t have any soft tissue on it. You’ll be able to skip this step. But, if you are dealing with fresh kills or roadkill, you’ll have to remove all the tissue before proceeding to whitening.
There are 6 main ways of doing this. I’ll go over them briefly here. For more detailed instructions, read this post on how to remove soft tissue from bones.
Method 1: Maceration (Soaking)
This invovles soaking the bones in water for weeks or even months. The water softens tissue and microbes in the water eat away at tissue. It’s very effective at removing hidden tissue in skulls without damaging them.
Method 2: Burying
When you bury bones, microbes in the dirt will eat away all the tissue. This is great for rotting carcasses, or if you are squeemish and don’t want to deal with stinky, gross tissue. The only main problem is that you can easily lose bones in the dirt, especially from small animals .
Method 3: Insects/Leave in the Open
You can just put the carcass outside and insects will eat away the tissue. You have to put the carcass in some sort of cage to protect it from scavengers.
Method 4: Corpse in a Box
With this method, you put a small corpse in a box that has holes in it. Insects will get to the carcass and eat away the tissue.
Method 5: Simmering
If you have a fresh kill with all of its tissue on it, simmering (not boiling) will loosen tissue so you can scrape it off.
Method 5: Steaming
Small carcasses can be put in a steamer. The steam will loosen tissue without damaging the bones.
Boiling: NOT Recommended
Despite what a lot of websites say, you shouldn’t boil bones to remove tissue. Boiling can damage bones and trap fat inside of them.
Isabel got this pig skull as a gift. It was boiled so got all gross, yellow and shiny from the fat that got trapped in it. It was HELL to degrease!!!! Lesson? DON’T BOIL BONES!
Step 3: Pre-clean the bones
This applies to bones you have found which do not have any soft tissue on them, but are caked with dirt and maybe have moss growing on them.
Use soapy water and the toothbrush to SCRUB the bones clean. The cleaner they are when you start, the better the hydrogen peroxide will work.
This gives a new definition to brushing your teeth!
Step 4: Degreasing
Degreasing is one of the most confusing steps in cleaning animal bones. It involves soaking bones in a solvent (like dish soap) to remove fat.
How do you know the bones need to be degreased? You’ll need to degrease if:
- The bones are yellow, clear, or shiny
- The bones stink, even after all tissue has been removed
- If the bones are from certain animals like: bears, pigs, boars, possoms, or seals.
It can take months for all the grease to get out of bones. If you skip this step though, the fat can slowly leach out of the bones and turn them yellow over time. They might even start to rot!
For more detailed instructions, read this post on How to Degrease Animal Bones.
Check out how greasy this possom skull is! It had to be thrown away because the fats started rotting the bone.
Step 5: Whiten with Hydrogen Peroxide
Once the bones are completely free of tissue and have been degreased, you are ready to whiten them. You’ll need hydrogen peroxide for this. As I said before, never use bleach for whitening bones. It will destroy them by making them flaky and brittle.
Here’s how to do it:
- Put the bones in your bucket.
- Pour in your hydrogen peroxide.
- Then top it with water.
- The bones will start foaming, which means the hydrogen peroxide is working. Hydrogen peroxide also heats up when it is working.
- Loosely coverthe boneswhile they soak. The H202 will stay active longer this way.
- Let the bones whiten for about 24 hours. Repeat if necessary.
How much hydrogen peroxide to use?
I usually use a ratio of 1:3 hydrogen peroxide to water. However, the higher the concentration of hydrogen, the faster and whiter your bones will be.
Tip:Try to find a container which fits your bones exactly. Then you won’t have to use as much H202 to cover the bones. If you can’t find a suitable container, you can use this pro trick:
- Line the container with a heavy-duty trash bag
- Put the bone in the trash bag
- Fill the container with water. The water will fill the space around the bone in the bag.
- Now pour the hydrogen peroxide into the trash bag.
Remember that hair developer works just the same as hydrogen peroxide. You can buy it in bulk here.
Adding peroxide to the bones
The peroxide is starting to foam!
How long to let bones whiten?
In general, I soak bones in hydrogen peroxide for 24 hours. This is usually long enough to get them white to my liking.
It’s important to note that I’m not going for pure white. If you want your bone specimens to berealllly white, then you’ll have to do several rounds.
*Note about Cleaning Very Dirty Bones
I once made the mistake of not adequately cleaning a very dirty bone. The hydrogen peroxide went crazy on it! It started steaming and got HOT. I thought it was going to melt the plastic bag it was in!!! You can see in the picture all of the steam coming off the bone.
The message? Make sure you do a really good job of scrubbing dirt off the bones before soaking in hydrogen peroxide!
Check out the steam coming off this dirty bone!
Before/After Pictures
These pictures should give you an idea of what realistic results you can expect when whitening bones with hydrogen peroxide. As I mentioned, you can do multiple soaks in H202 to get them whiter.
Dog Skull
Here’s a giant dog skull that a friend found for me. It had been sitting in the woods for a long time and was very dirty. I did one soak in 40v hair developer to get it whitened.
Greasy Pig Skull
This pig skull was given to us as a present. It had been boiled to remove the tissue (which is a bad idea!) so there was tons of fat trapped in the skull. I had to degrease it for 2 months and then whiten it before it got to this state.
A Very Dirty Hip Bone
This hip bone was found in a river and was covered with dirt and moss. Considering how dirty it was when I found it, the bone came out nice and clean.
Cat Skull
This old cat skull was found in the woods and soaked in 40v hair developer for 24 hours.
Vertebrae:
This vertebrae stunk like crazy from all the fat trapped in it (notice the shiny parts on the before photo). I degreased it in acetone and then did a hydrogen peroxide soak. It came out nice and white.
Tips for Very Large Skulls or Bones
One of the first large skulls I cleaned and whitened was a cow skull. Isabel’s friend found it for her (what other 6 year old is lucky enough to have a friend who saves bones for her?). The skull was free of soft tissue, but was still really dirty and stunk badly. I didn’t realize it smelled so badly until halfway home on the bus. Sorry to all the people who had to put up with the rotting smell on the 30 minute bus ride! 😮
Cleaning such a large skull presented some problems:
- I literally could not find a plastic container large enough for soaking the skull. Not even laundry baskets were wide enough to fit it.
- I would have had to use TONS of hydrogen to immerse the bone. I’m not a rich person and wasn’t thrilled about spending $50+ on peroxide for a skull.
Luckily, there are some solutions for these issues.
Trash Bag Trick
Here’s a pro trick to use less hydrogen peroxide when whitening large skulls:
- Fill a trash can with water
- Then put the skull in a sturdy plastic bag into the water.
- Pour your hydrogen peroxide/water solution into the trash bag.
- Since the water fills the empty space around the skull and pushes on the bag, you won’t need as much hydrogen peroxide to emerse the skull.
Unfortunately, I didn’t know about this trick or have a trash can large enough to hold my cow skull. So, I put the skull into a big trash bag, poured in some hydrogen and water, and then tied off the bag. I kind of propped everything up in a plastic drawer.
Of course the trash bag sprung a leak. The peroxide pooled at the bottom, so only part of the skull got whitened. You can see a line on the skull from the part which was sitting in the most hydrogen solution. It looks terrible!
Notice the whiter line from my first attempt at cleaning the skull.
Baking Soda + Hydrogen Peroxide Paste
Baking soda is a natural cleaning agent, right? Could I mix it with hydrogen peroxide to form a paste, and then spread the paste on the bone?
I did a small test batch. The baking soda and hydrogen foamed a bit when mixed up, but still formed a paste that could be spread onto the skull. *You can buy cheap hydrogen peroxide here.
This is the paste I made from baking soda and hydrogen peroxide. It was about as thick as toothpaste.
The great thing about the paste method is that you don’t have to use lots of hydrogen peroxide and it can be spread in all those weird nooks and crannies skulls have. The only annoying thing is that you will have to do at least two rounds – one for the top of the skull and another for the bottom.
Applying the paste to the skull. It started foaming quickly, but the paste didn’t fall off.
Here you can see what it looked like afterwards. A huge difference!
Paint On Cream Hair Developer
As I mentioned before, cream hair developer has emulsifiers added to thicken it. What’s cool about this is that you can paint it directly onto bones. There’s no need to mix it with baking soda to thicken it! After applying, cover the bones with plastic wrap. Otherwise the cream developer will dry out too quickly.
Like with the baking soda paste, this method also won’t clean the interior of the skull. Make sure your skull is completely clean of tissue before you try to whiten it by painting on cream developer.
Pig skull with cream hair developer painted on it.
Want more tips on how to clean bones?
Have questions about antlers, horns, beaks?
Want to know how to glue together bones?
These are all things I talk about in my eBook. Get it here for $4.99.
FAQs
How do you whiten animal bones for display? ›
Cover with a 50/50 mixture of hydrogen peroxide/hair developer and water. Make sure that the bones are fully submerged. Cover loosely with a lid and let sit for 24 hours. After 24 hours, check on your bones and if you are happy with the whiteness, rinse thoroughly and let dry.
How do you whiten animal skulls? ›Place in hydrogen peroxide
Use 5–10% hydrogen peroxide. Remember to use gloves and protective goggles. Leave the skull in the hydrogen peroxide until it has reached the desired whiteness. For a deer skull, this usually takes 24 hours.
Leave bones in peroxide for about 24–48 hours, then remove and let them dry for several hours. Bone can appear much darker than expected just from being wet. Chlorox bleach destroys bone structure, and eventually leads to a crumbling and yellowing specimen.
Does rubbing alcohol whiten bones? ›It won't whiten, but you can use it to preserve small intact specimens.
How long does it take for hydrogen peroxide to lighten dark spots? ›You can use hydrogen peroxide to lighten acne scars, age spots, and other skin discolorations. Use a cotton pad to apply a thin layer of peroxide to the affected area. Let it sit for 10 minutes, then rinse with water. Over time this treatment will lighten those spots and make them much less noticeable.
Will 3 peroxide whiten a skull? ›Some bleaching is probably best, but not enough to make them completely white. Air-dried skulls may be bleached by soaking them in an approximately 3% to 6% solution of hydrogen peroxide. Hydrogen peroxide solutions that are used to bleach hair can be purchased from beauty supply stores.
Can you clean bones with vinegar? ›NOT Recommended for Sterilizing Bones
And, while some people do boil bones to get soft tissue off, it generally isn't recommended. The high temperatures can soften and destroy the bones, especially smaller bones. Vinegar: Vinegar will dissolve and soften bones. Plus, it isn't even a good disinfectant.
After the skull is as clean as you can get it, soak it in an enzyme-bleach powder (such as Biz) using about ¾ cup to a gallon of water. Don't use liquid bleach, it is harsher to the bone and does not have the enzyme action that is needed to break down residual tissue.
What is the best way to clean bones? ›- 1 Wash Bones. Wash your animal bones with slightly soapy warm water, rinse, and set it aside.
- 2 Add Water to Container. Fill the plastic container with enough water to submerge the bone, but leave enough room that you can put your hands in without spilling.
- 3 Add Cream Peroxide. ...
- 4 Stir. ...
- 5 Soak. ...
- 6 Brush Lightly. ...
- 7 Dry Bones.
In Experiment #1 Vinegar dissolves the calcium, or apatite, in the bone, leaving only the protein, or collagen, so you can bend the bone. After a few days of soaking in vinegar, almost all the calcium in the first experimental bone is gone. The bone become soft and rubbery.
What happens when you soak a bone in bleach? ›
Bleach can remove any excess tissue from bone without a doubt, but it will damage the skull itself in a very permanent way. Skulls treated with bleach become chalky and porous because the bleach has broken down the structure of it, this means the bone will eventually deteriorate into dust.
How long should bones soak in bleach? ›Do not breathe bleach fumes, which can hurt your lungs. Let the bones soak for 24 hours. Place each bone back in its cup.
Can I use hydrogen peroxide to clean bones? ›Once you are sure your bones will fit in your container you can begin to submerge them in a 1:3 mixture of hydrogen peroxide to water. You'll know it's working when you see the bones starting to bubble, foam, and may generate a bit of heat. This means the H2O2 is doing its job and deep cleaning the bones.
What happens when you mix rubbing alcohol and white vinegar? ›Using isopropyl alcohol and white vinegar together makes a quickly evaporating spray glass and mirror cleaner that competes with national brands. This can also be used to give a nice shine to hard tiles, chrome, and other surfaces.
Can baking soda clean bones? ›Create a peroxide and baking soda paste to clean really big bones. Sometimes you might come across a bone that just isn't going to fit into any container you have. When this happens, get a large plastic bowl and put in 1 cup (160 grams) of baking soda. Add just enough hydrogen peroxide to create a thick paste.
What removes dark spots the quickest? ›- 2% hydroquinone.
- azelaic acid.
- glycolic acid.
- kojic acid.
- retinoids, such as retinol, tretinoin, adapalene gel, or tazarotene.
- vitamin C.
Does baking soda help remove dark spots? A. Owing to its bleaching properties, baking soda can help fade away black marks and spots on the skin. However, it's important that you mix baking soda with other natural ingredients as it can be harsh on your skin if used topically.
Can peroxide get rid of dark spots? ›The hydrogen peroxide helps moisten age spots to dissolve them without damaging surrounding skin. Some people need more than one treatment in order to dissolve an age spot completely, especially if it's large or very dark.
Is peroxide good for white heads? ›Many people have tried hydrogen peroxide for acne because of its antibacterial and drying properties. However, there is no evidence to prove that it can clear acne. In some cases, hydrogen peroxide could make acne or scarring worse. There is also a lack of evidence to show that it's safe to use as an acne treatment.
What does 3% hydrogen peroxide do to hair? ›Hydrogen peroxide is sold in drugstores and grocery stores at a low concentration, usually at 3 to 9 percent. It can be used as a disinfectant and as bleach, including as a hair lightener. Because of this, hydrogen peroxide is an ingredient in many blonde hair dyes.
Can I put hydrogen peroxide on my head? ›
It can be used as a disinfectant and as bleach, including as a hair lightener. Because of this, hydrogen peroxide is an ingredient in many blonde hair dyes. While it's generally safe to use hydrogen peroxide* on your skin and hair, it can cause skin, lung, and eye irritation.
How do you whiten a deer skull with 40 peroxide? ›Instead of actual bleach, hydrogen peroxide works much better to whiten the skull and does not compromise the bone density like bleach does. With 40-vol peroxide (available at any beauty supply store), use a paintbrush and apply a healthy coating all over the skull. Be careful not to get any on the antlers.
How do you preserve dead animal bones? ›Once you have mostly bone, put the bones in a bucket of water or a glass jar, close it—but not too tightly, as a lack of oxygen will slow down the process—put it in the sun, and leave it. This is called maceration, which is a sped-up rotting process whereby the bones are cleaned by bacteria.
How do you whiten a deer skull with baking soda? ›- Measure 3/4 cup baking soda into a non-porous (metal, glass or ceramic) mixing bowl, or a disposable dish. ...
- Add a cap full of bleach to the baking soda at a time. ...
- Apply the paste to the animal skull using a small craft brush.
Can You Mix Hydrogen Peroxide and Bleach? Like any other household cleaner or chemical, hydrogen peroxide is another thing you shouldn't mix with bleach. It can create toxic gases that are dangerous to anyone in the area.
How do you clean and preserve an animal skull? ›Cold water maceration is a long process that involves letting the skull soak in room temperature water with a small amount of cold-water laundry detergent. These detergents have enzymes that will break down organic matter. This is the safest way to clean the skull and leave it intact.
Can you use oxiclean to bleach a skull? ›Turn off heat and remove from burner, place skull in hot water, add Oxiclean 1 tablespoon at a time. It only takes a small amount. For the deer skull, I used about 1/4 cup. NOTE: Adding the Oxiclean begins an immediate enzymatic process.
Should you bleach bones? ›Why/When to Whiten Bones. Whitening is not a necessary step when cleaning bones, but it does sanitize them and give them a nice clean-looking white finish. If you prefer the natural color of bone but still would like to sanitize them, you can put them in low percentage peroxide for an hour or less.
Do animal bones carry diseases? ›Raw meat and bones can be contaminated with a number of pathogens, including E. coli, Salmonella species, and Listeria. These pathogens may or may not make a dog sick, depending on the dog's health status, but pose a significant health risk to the humans in the household.
Does vinegar destroy calcium? ›White vinegar is a natural solution that can be utilized to dissolve calcium buildup. Sitting overnight, you will be able to remove lime buildup from the drain while avoiding the harsh chemicals in traditional drain cleaners. Avoid putting any store-bought chemicals down the drain.
What happens when you put a bone in Coke? ›
Coke softens your bones (actually, they make them weak and brittle) in three ways: Carbonation reduces the calcium in the bones. Phosphoric acid reduces the calcium in the bones. The beverage replaces a calcium-containing alternative, such as milk or water.
Does hydrogen peroxide dissolve bone? ›Peroxide will not dissolve soft tissue or flesh but it can soften the tissue to make it easier to remove. It also sterilises the bone.
How long to leave peroxide on deer skull? ›Set the skull aside and let the Bleach Agent and Hydrogen Peroxide whiten the skull. This will take 18 to 24 hours. With a clean, dry paintbrush dust off the dried mixture from the skull.
What happens when a bone is soaked in water? ›The bones soaked in water will remain bone brittle. Removing enough calcium to yield “rubber bones” will take several days. Leg bones may take a week or more.
What happens if you mix white vinegar and baking soda? ›The two products generate quite a reaction. When vinegar (dilute acetic acid) and baking soda (sodium bicarbonate) mix together, the pair "foams up" to produce carbon dioxide gas, as well as liquid water, acetate ions and sodium ions. The carbon dioxide gas is what produces the bubbles.
What happens when you mix rubbing alcohol and salt? ›Salting out isopropyl alcohol increases the potency of the alcohol by using salt to draw the water out of the alcohol. The salt dissolves in the water, but is insoluble in isopropyl alcohol, making the water heavier and separate to the bottom while the isopropyl alcohol floats on the top.
Can you mix rubbing alcohol with vinegar and dish soap? ›For a better, green solution that is cheap and friendly to the environment, use VINEGAR! Pour vinegar full strength, or mix it up! Here's a good recipe to try: Combine 1 / 2 cup white vinegar, 1 pint rubbing alcohol and 1 teaspoon liquid dishwashing liquid.
How long to soak bones in dish soap? ›Mix a solution of water and undyed dish soap, and let your bones soak for several days. Still gross? Repeat the process. It's important that your dish soap does not have dye, or your bones may become stained that color.
How do you clean a deer skull without boiling it? ›Beetles. One of the easiest means of cleaning up a deer skull is to let beetles do the dirty work for you. Flesh eating beetles make this a hands-off method of getting your skull cleaned up. You simply drop your skull into the bin with the beetles, and let them go to work.
What is the best degreaser for bones? ›Ammonia is a great degreasing agent and has the benefit of being cheap. You can often find it in hardware stores. Just make sure that you get the clear ammonia and not one that is colored as it might have additives which can harm the bone. Most ammonia in stores is 2.5% strength.
Can vinegar clean animal bones? ›
NOT Recommended for Sterilizing Bones
And, while some people do boil bones to get soft tissue off, it generally isn't recommended. The high temperatures can soften and destroy the bones, especially smaller bones. Vinegar: Vinegar will dissolve and soften bones. Plus, it isn't even a good disinfectant.
After the skull is as clean as you can get it, soak it in an enzyme-bleach powder (such as Biz) using about ¾ cup to a gallon of water. Don't use liquid bleach, it is harsher to the bone and does not have the enzyme action that is needed to break down residual tissue.
How do you clean bones for carving? ›The inside and outside of the bones need to be scraped with a knife to get rid of the attached meat and tendons. After that, they must be soaked in a mixture of about 2 quarts of water, 1 cup of bleach, and 1 cup of laundry detergent overnight. This helps clean the bones and prevent oil stains from setting in.
What does soaking a bone in vinegar do? ›In Experiment #1 Vinegar dissolves the calcium, or apatite, in the bone, leaving only the protein, or collagen, so you can bend the bone. After a few days of soaking in vinegar, almost all the calcium in the first experimental bone is gone. The bone become soft and rubbery. You can even tie it in a knot!
What happens when you leave bones in vinegar? ›In this activity, vinegar, an acid, will slowly dissolve the calcium in the bones, making the bones weak.
Can you clean animal bones with baking soda? ›Create a peroxide and baking soda paste to clean really big bones. Sometimes you might come across a bone that just isn't going to fit into any container you have. When this happens, get a large plastic bowl and put in 1 cup (160 grams) of baking soda. Add just enough hydrogen peroxide to create a thick paste.
How do you clean bones with Dawn? ›Degreasing. Bones have a natural 'greasiness' due to fat and other grossness that comes with having at one point been a living being. Mix a solution of water and undyed dish soap, and let your bones soak for several days.
Will peroxide bleach deer antlers? ›You can spray a bit of hydrogen peroxide onto them and then scrub. This will help remove stains and discoloration. However, the hydrogen peroxide will also whiten the antlers a bit, which ruins their natural color.
Will bleach hurt a deer skull? ›Bleach can remove any excess tissue from bone without a doubt, but it will damage the skull itself in a very permanent way. Skulls treated with bleach become chalky and porous because the bleach has broken down the structure of it, this means the bone will eventually deteriorate into dust.
What do you put in water when boiling deer skulls? ›Add one box of baking soda and ½ cup of Dawn detergent to the water, and bring to a simmer. The baking soda will help soften the tissue, the Dawn will help break down any grease. A rolling boil will cook the skull too fast, compromising the integrity of the bone.