Degreasing 101- Three Ways to Turn Yellow Bones White

What is Degreasing?

In terms of cleaning bones, degreasing is the process of removing the natural oils and fats from bones so they are no longer yellow, translucent, or waxy feeling.

What Materials are Needed to Degrease Bones?

1. Flesh-free bones (see Maceration 101 if your bones aren’t flesh-free yet)

2. A waterproof and/or acetone-safe container that can be sealed

3. At least one of the following:

4. Recommended: Aquarium Heater or Bucket Heater

5. Recommended: Strainer to not lose bones

6. Acetone-safe Respirator and Gloves

7. Water

8. Recommended: Mesh Bags

Click Here to See a Full list of Supplies I Use to Process and Articulate Bones with Reviews of Each of Them

Why/When to Degrease Bones

Grease in bones can cause them to be sticky, discolored, or smelly. If your bones are displaying any of those signs, you likely need to degrease them. Grease can be noticed in bones by them being translucent (almost making the bone look wet), or it can be an array of colors including yellow, orange, brown, and various shades in between. 

how to degrease bones
This is a red fox skull that needs to be degreased. The majority of the skull is white and degreased, but these two sections near the back molars show a lot of grease.

You will never be able to have a white, clean skull if it has grease in it. Some grease can be seen on the surface of the bone, and other grease can be deep within the bone and not be visible for months until it surfaces. This is why it is important to not put any coating on bones (including paint) until they are completely degreased. Deep grease can surface later, showing up trapped under lacquer or messing up paint.

How Long Does Degreasing Take?

This is the question I hear the most, and the simple answer is, it takes however long it takes. Degreasing is almost always the longest step of processing animals, and there is no quick way of doing it without damaging the bone (we’ll cover why not to boil/simmer bones in peroxide or oxyclean to “degrease” them at a later time.) Some lean animals (often young animals) occasionally do not need to be degreased at all. Others like bear, boar, elephant feet (personal experience), and other fatty animals can take many many months to finish degreasing. In my personal experience, cats usually take about a month to degrease, and dogs can take 1-4 months depending on the breed and how fat they were. These time frames are just an average of what I’ve dealt with. Some may take a week, others may take 6+ months. It really just depends on the animal.

Degreasing Method 1: Soap and Water

Arguably the easiest and cheapest method of degreasing involves some water, dish soap (Dawn recommended), and heat (recommended.) This is the method that most beginners will use at first, as the materials are easy to find around your house. All you need to do is mix some Dawn (For my international readers: Dawn is a name brand of dish soap in the US. “Fairy Liquid” is another name for it overseas- just find a dish soap that removes oils) with water (there’s no set ratio of dawn to water, just make it bubbly), place your bones in, and keep it hot. There are several ways to keep the container hot, such as using a heater– link to the one I recommend for 5gal buckets. The heater is a bit pricey ($50-60), but they last a very long time (I never had one burn out) and work very well. Ideally you want the temperature anywhere between 80-115F (26.6-46C) If you forget that the thermostat is in Celcius and accidentally set it to 80-115C you will melt your bucket and potentially start a fire.), aquarium heater (you’ll have to bypass the temperature controls to get it hot enough), placing the container outside on a hot day, or placing the container near something that will keep it warm. Different animals’ fats break down at different temperatures, but keeping it around or below 115F (46C) will cover most fats. 115F is not too hot for bones (we will cover the effects of higher temperatures in another article), but if you’re not able to get it quite that hot it’ll still work. Room temperature is not recommended for the dish soap method, as heat will thin the grease and speed up the process. It’ll still work at room temperature, it’ll just be much slower.

Clear dawn is best to use, as it will allow you to see the bones better, easily show if yellow grease is coming out, and you have a 0% chance of staining the bones. I know several people who have ended up with blue bones from using blue Dawn to degrease. You may also use other brands of soap, though Dawn is known as one of the better dish soaps to use. Avoid using detergent of any kind (including borax, baking soda, oxyclean, or anything similar) as they are not effective degreasers or can damage the bone.

When your soap water mixture turns cloudy or yellow, its time to change it out (roughly once a week.) Simply pour it out, wash off the bones, and refill with fresh Dawn and water. Repeat the process until the bones no longer appear greasy.

Degreasing Method 2: Ammonia

This method is very similar to the dish soap method, this one just uses ammonia instead of Dawn. I personally have used this method the past several years, and it works very well. You can use concentrated ammonia from a hardware store (usually 10-30%) or very diluted clear household cleaning ammonia from Walmart or a dollar store that is 2.5% strength (doesn’t say the percentage on it- I had to look it up). If you’re using the concentrated stuff you can use it straight or dilute it. I used to use the cheap 2.5% stuff from Walmart, and then dilute it even more. Now I buy the 10% concentrated ammonia from Ace Hardware and dilute it down to 2.5%. Rough ratio I use is a half gallon of 2.5% ammonia to 10 gallons of water. Buying it from Ace saves a few dollars and keeps you from having a million half-gallon jugs lying around. The fumes from the 10% are extremely strong, so make sure to use a respirator with a shield to cover your eyes. Supposedly you can use the strong stuff without heating it, but I personally use the diluted and then heat it to 112F (44C) with a heater– If you forget that the thermostat on this heater is in Celcius and accidentally set it to 80-115C you will melt your bucket and potentially start a fire.) Make sure not to use the lemon scented ammonia! It can stain bones, and is very hard to tell when it’s time to dump it. Use the same steps as the dish soap- change it out when it gets cloudy, yellow, or when grease is floating on top (I change my degreasing buckets once a week.)

Use caution when using ammonia as it very easily irritates your nose and eyes. Try not to breathe in the fumes, as it will take your breath away (but open up your sinuses!) Ammonia is used to wake up people that pass out- the stuff smells STRONG. The fumes from the 10% are extremely extremely strong, so make sure to use a respirator with a shield to cover your eyes. If you’re using the 2.5% ammonia you can wear a respirator (without the face shield) if you’d like, but the fumes aren’t near as strong as the 10%, and don’t have negative health effects like acetone does.

how to degrease bones
Sometimes you'll find this- the water appears clear, but there are literal oils floating on the surface. Still time to change out the liquid.
how to degrease bones
This is after degreasing in heated ammonia for one week. The ammonia water was clear when I put it in. This means the bones are extremely greasy, but the degreasing process is working very well.

Degreasing Method 3: Acetone

This is the most expensive, but least labor intensive method. This is not a method for beginners, as special equipment is needed to work with acetone, and it has negative health effects and is a safety hazard. You will need airtight acetone-safe containers to keep the acetone in. Acetone dissolves many plastics, so you’re safest using glass containers. If you’re using a plastic container, make sure that it says HDPE on the bottom-  HDPE plastic is acetone-safe. The container has to be airtight, as acetone evaporates very very easily. You’ll also need acetone-safe gloves (Butyl Gloves are the most common) and a respirator for organic vapors. Regular nitrile or latex gloves will quickly fall apart when exposed to acetone. Acetone will dry out your skin, and is not good to breathe. It’s also extremely flammable, so it will need to be kept in a cool place, far far away from any source of heat or spark. The fumes travel easily and can very easily ignite with a small spark. Only work with acetone in a very ventilated space.

Now that the safety aspect is covered, we can move on to the usage. Using acetone to degrease bones is very simple. Simply place the bones in it and wait.  You cannot dilute acetone, and at roughly $14.65 a gallon (at Walmart) it makes it quite expensive to use to degrease larger things. Do not heat the acetone, it works just fine at room temperature. Acetone does not need to be changed out near as often as the other two methods, as it can be reused many many times until it turns a dark orange color, at which point it will no longer dissolve any grease. I usually have to retire acetone after about 3-5 months of use.

how to degrease bones
Huge elephant foot and cassowary leg bone (both zoo animals that I was working on) in 7 gallons of acetone. The foot took over 5 months to fully degrease.

Another negative part of using acetone is you cannot pour it down your drain like you can Dawn or ammonia. Acetone needs to be taken to a proper disposal place (places that accept grey water usually accept it), so you’ll have to find a place near you to dispose of it when you’re done using it. Make sure to let any bones that were in acetone COMPLETELY DRY before whitening them. Acetone reacts very violently with peroxide, so make sure they never come in contact with each other.

Which Method is Best?

There is really no superior degreasing method. I personally use heated diluted ammonia or acetone (not heated), but many many people swear by the Dawn method, which also works! Experiment with different methods and see which one you prefer. Acetone doesn’t need to be heated like the others, but is also dangerous to work with and requires special equipment. There’s also many other methods of degreasing that are not covered in this article (such as using horse manure to degrease bones!) I simply wrote about the three that I have experience using.

Tips and Tricks

Degreasing takes forever, there’s no getting around that, but there are a few things that you can do to slightly reduce the degreasing time. 

  1. The first of which is to not rush maceration! Macerating bones drastically helps in comparison to beetling bones. Maceration bacteria begin to degrease the bones inside as the flesh is being eaten away on the outside, whereas beetled bones are usually very greasy from the fats drying and oils soaking into the bones while the beetles eat the meat on the outside. Leaving the bones in maceration for an extra week won’t hurt anything, and can actually cut down on degreasing time by eating away the fatty marrow inside the bones.                                                             
  2. Drill small holes in the long bones (leg and arm bones) for the marrow to get out! There are two types of bone marrow- red and yellow. Red marrow is where the majority of your blood cells are made, and yellow marrow is where a lot of fat is stored. If the marrow does not come out of the bones and ends up drying, it can lead to them looking dark or greasy. Macerating and degreasing usually eats all of it without drilling, but drilling a small hole in each side of the bone drastically helps get it out. If you’ll drill the holes in a freshly macerated bone and then run water in one side you can literally see the liquefied marrow run out. So it’s not a necessary step, but in my experience it helps. Just drill the holes in hidden spots, or where you plan on having a drill hole anyway if you plan on articulating.                                                                                                  
  3. Cycling between degreasing and whitening! I personally cycle between ammonia, peroxide, and acetone to help degrease super greasy animals. I’ll do a few weeks of degreasing in ammonia, let the bones completely dry, put them in peroxide for a few days (Read our Whitening Guide if you haven’t already), let the bones completely dry, degrease in acetone for a few weeks, let them dry, rewhiten, let dry, repeat. After the bones dry after a peroxide bath it’s much easier to spot any leftover grease. I also think cycling ammonia (or Dawn) and acetone works really well as ammonia and Dawn thin the grease, making it easier for the acetone to dissolve it. Just make sure to let the bones COMPLETELY DRY between baths. As I said earlier, acetone and peroxide do NOT mix well together.                                                                                                                                  
  4. You can keep your bones in Mesh Bags to make sure you don’t lose any bones, and so you’re able to degrease multiple animals in one container- saving space and chemicals! I personally have several hundred of these bags, and I LOVE this company. The bags have a lifetime warranty, so if any stitching comes undone, just send them an email and they’ll send you some new ones. I’ve actually spent so much money on these bags that the company decided to Sponsor me and give me a small portion of all sales that come from this blog! So if you want any mesh bags (small, medium, or large- I use all of them) and want to help me afford my unhealthy obsession with buying more bags, please use the link above to purchase any!

What Do I Do Now?

Well, if you’re happy with your degreased bones, you don’t have to do anything else! If you’d like to whiten your bones, you can move to the next guide, Whitening 101,  if you’d like, but that is not required if you’re happy with the natural color of the bone.

If you found this article helpful, feel free to leave a comment down below or share it with your friends! I don’t get anything directly from making these guides, but it saves me time answering questions and helps you all so I’ll continue to do it! I don’t ask for/accept donations, but feel free to grab something small from my Shop or follow me on my social media (InstagramFacebook, or Tumblr) if you’d like to support my work!

If you noticed any typos while reading this, any links don’t work, or have any suggestions or questions that weren’t covered in this article or the other articles on my Blog, please leave a comment below or Contact Me

I’d like to give a very special thanks to Suzy G. for letting me use the before and after picture of her Opossum skull in this article. You can visit her etsy store by clicking here.

how to degrease bones
Here's a before and after of an opossum skull that was degreased by cycling acetone and dishsoap. Very special thanks to Suzy G. for allowing me to use this picture of hers!

46 Responses to “Degreasing 101- Three Ways to Turn Yellow Bones White

  • very helpful + very well-written, thanks!

  • I think you did a great job covering a large amount of information I’ve been hard pressed to find thus far. One question, you touched on minimally young skulls vs adults…i have a young goat skull which you stated may not require decreasing methods that adults require. Could you please elaborate on that and how i can be sure since ive already began encrusting my skull in amethyst. Thank you!!

    • Hey, Holly,

      Young animals usually are not as greasy as adults. After you’re done macerating and whitening it if there’s no signs of grease (yellowing, translucent spots, etc) then the skull may not require additional degreasing

  • i have a grizzly bear skull that is of a yellow color soon after removing the flesh via partial boiling.
    i am currently letting it soak in dawn water but i can only heat it once or twice a day via poring hot water into the bucket which then eventually cools i am wondering if i am only wasting my time and damaging the skull?

    Is it possible to put it in a pot with dawn dish soap on the stove that is below boiling and carefully watch it for a day to help speed it along ?

  • Rebecca Gebhardt
    4 years ago

    I’m so glad I found this page! I had so many questions since I’m new to this. It’s hard to find good information on the internet. I’ve been following your IG account and just realized it’s the same person! I love your work. Thanks for all the help!

  • thanks for the info! wondering if you can help me… I’ve noticed that some of my bones are extremely soft coming out of degreasing, in some cases they practically turn to paste if pressure is applied. why is this happening? is something damaging them? will they regain their strength after drying out? anything I can do to make this better? thanks for the great info and any help ?

    • Hey cm,

      That’s definitely not normal! I’ll need some more info in order to help. What animal(s) is this happening to? Are they young animals? What method are you using to degrease? What temperature are you using? Once you answer these hopefully I can help you out!

      -Dalton from OddArticulations, LLC

  • I am wondering if any of these methods will work for small birds? I have a lot of dead pigeons in my yard because my neighbor likes to feed them and the local hawks hunt them. I am wanting to collect and clean these bones. Most just have little bits of flesh and feathers left. So after they finish the natural decomposition process I would like to degrease them and bleach them. Which method would you recommend for city pigeons? And about how long do you recommend they soak? I have looked everywhere online and not a lot of people have no on cleaning and preserving bird bones.

    • Hey Tayler,

      The main reason you don’t see cleaning guides tailored to birds is because almost all of them are protected under the Migratory Bird Treaty Act of 1918 and are thus illegal to possess. This includes bones, feathers, egg shells, and even abandoned nests. You’ll have to determine what species of pigeon you have before you’ll know if you can legally keep and clean them. But yes, if they’re legal to keep these guides will work for cleaning them. If they still have flesh on them you can start by macerating, and then use any of these degreasing methods and then move on to whitening with peroxide. Timelines vary, so you’ll just need to soak until they’re done.

      Hope this helps!

      • Hi! This might fall under the maceration portion but I’m not sure so I’ll ask!
        I found a doe skull and decided to take it home to clean. I immediately put it in a dawn and peroxide bath to degrease and whiten (JUST learned you shouldn’t do these steps together). I went to change out the water and remove the veins (didn’t get ALL but most of one vein) and I noticed that the skull was mostly covered in a layer of membrane. I was able to remove most of it but there is still membrane that I cannot remove from all the cracks where bones meet and other odd places where it just will not budge. I was wondering if I could macerate it. It’s got no true flesh, only membrane. The thing is is that I live in an apartment in the city and have no place to macerate so I just have it soaking in water in a sealed container in my bathroom. I don’t have a heater for the bucket but even after one night of clear water (after a week of peroxide, it got NASTY in the dawn and peroxide) it is already getting cloudy. Will this work to remove those bits of membrane? I tried and there’s NO WAY to remove them via scalpel. Please help!

        • Hey Ryan,

          Degreasing will loosen up tissues, but maceration is better at literally eating them away. For your skull if you decide to try macerating it you likely will need to boost the bacteria culture by throwing in a scrap of meat or something. Hope this helps!

        • Thank you so so much! If you’re curious to see pictures (or if you think they may help someone else out) of my progress let me know!

  • Very clear instructions that anyone can follow and using standard supplies! Well done!!

    My method for degreasing combines degreasing and maceration at once…kind of.

    After stripping off as much muscle as I can I place my bones into a pot of cold water mixed with trisodium phosphate. I used to use Soilax, but that is gone and i have been using a Savogran product simply called TSP. (https://i5.walmartimages.com/asr/0c3ac03f-c6e2-478c-bdb6-f6204fe38066_1.eeb71eebd2382278f8e5110a2422109d.jpeg)

    I bring the pot to the boil, then reduce to simmer for up to an hour. The TSP seems to jellify the meat and draw the grease from the bone at the same time. The water level must be well above the bones so that the fats can float above the bones.

    I like to do a second boil/simmer/soak for things like bear or raccoon skulls. These species have a lot of grease in them and the second soak really helps.

    After the water cools I put in a drop of Dawn dish soap to scatter the floating oils to the sides of the pot and retrieve big bones through the clear water in the center. Then I pour off the water to get rid of the fats, and retrieve all the small bones or teeth that have fallen out.

    The results is squeaky clean bones ready for bleaching, sealing and assembly for display.

  • Thanks so much for this! Just one quick question, I’m eager to try using the mesh bags (I recently soaked three skulls together and trying to sort out the teeth has been… fun), but do they hold up okay in the acetone or do they disintegrate in there? I’m trying to decide going forward whether I can use something like that or if I need to just get some smaller buckets and use a separate bucket for each skull.

    • Hey Mac,

      Acetone won’t mess with the actual mesh of the bags, but may start messing with the little black plastic slider piece that keeps the bags closed. Should be an easy test to see if that’ll happen, though. Hope this helps!

  • Thanks for the info! I was wondering if there are any differences degreasing fish bones?

    • Hey Matt, there’s not much different in terms of degreasing fish bones, though fish tend to be SUPER greasy and take many many months to over a year to degrease. Many people prefer to use acetone to try to keep the fish skulls together, but any of the methods discussed in the guide will work. Hope this helps! -Dalton

  • Bridget Ables
    3 years ago

    I have some bones that I have entirely cleaned
    They’re not smelly or discolored from what I can tell, but they’re kinda sticky, so I can’t tell if its from grease or not

    • Hey Bridget, without seeing them I won’t be able to tell for certain, but yes stickiness is often an attribute of very greasy bones. I’d recommend degreasing them some more and see if it helps

  • Tessa A hennigan
    3 years ago

    I acquired some beaver skulls that were more or less clean but needed to be degreased. I soaked them in dawn and water and am located in deep south texas so temps average 100+ almost year round. When I went to do a water change, I noticed some of the bones and teeth were black, not Slimy or anything but black black. On one, one tooth was black but not the other. Some look like they were partially submerged due to the way the black sits across a jaw despite them being totally submerged. I’m not sure where I went wrong or what happened since I’ve never had this happen, but this is my first time working with beaver. I usually work with rattlesnake.

    • Hey Tessa,
      You didn’t do anything wrong! It’s pretty normal for teeth (and sometimes bone) to turn weird colors as bacteria dies. Rest assured that the teeth will turn back to their lovely orange color after whitening!

  • Your guides have been super helpful so far! One question, while heating in the bucket is it okay to secure the lid? Or should the bucket be left open? I’m super paranoid about causing a fire or melting the bucket. Thanks!

    • Hi! Closing the bucket is fine. Unless a heater malfunctions you shouldn’t have to worry about a fire or bucket melting

  • Dan Heck
    2 years ago

    I’ve had good luck with lacquer thinner [not mineral spirits oil paint thinner] for degreasing. It’s not quite as volatile as acetone, but it evaporates away almost as quickly & very cleanly, with no oily residue or odor. One consideration: acetone is soluble in both fats and water, but lacquer thinner is not at all soluble in water. If the specimen still has a fair amount of water in it, the lacquer thinner may not be able to penetrate as well. I’d recommend using it only on dried specimens.

  • Steve Brady
    2 years ago

    I use bugs, dermistides, to clean then degrease in heated Dawn mixture. A 120v bucket heater with a remote bulb thermostat maintains temp. I keep a plastic bag over the bucket to retard evaporation.
    It can take along time to get a skull degreased. After I am finished, I keep the skull for a month or longer to be sure the skull stays white. I have begun to mix 35% peroxide to get 6% solution.
    I just mixed a “hot” batch to attempt to degrease preobital glands on two stubborn whitetails.
    I just stumbled across this write up….very good info.

  • Debra Whitall
    2 years ago

    Thanks so much for your well-written instructions. We purchased a beautiful carved water buffalo skull several years ago and have noticed in the last few months that it is discoloring in certain areas. Polyurethane has obviously been used. Based on your article we suspect that grease is surfacing. Do you have any suggestions on how to whiten it? If left untreated will it continue to discolor and disintegrate? Thanks for your help! Debra

    • Hey Debra,

      Yes over time it will continue to leech more oils and discolor, but as long as it wasn’t boiled or bleached it shouldn’t disintegrate. The ideal course would be to remove the polyurethane and then finish degreasing it, at which point you can whiten it with peroxide if you choose to do so. Test out acetone on a cotton swab on a non-visible part of the skull and see if that removes the polyurethane for you, if so you should be able to remove almost all of it prior to degreasing. Without removing it prior I would assume you’d run into some issues during degreasing from the grease either not being able to get through the polyurethane or it starting to discolor or come off in sections. Best of luck!

  • Debra Whitall
    2 years ago

    Thanks Dalton – we really appreciate your help!

  • This guide is so helpful, I keep coming back to it, thank you!

    I recently got a female pronghorn skull from someone who had already “cleaned” it, but it was pretty greasy. I soaked it in acetone, which definitely brought up the grease, but also when I pulled it out of the acetone I could see where I hadn’t noticed before that there are still a bunch of small bits of fatty tissue clinging to the skull, especially around the back where the spinal cord would’ve entered, and what looks like a big blood vessel running through the face. I’m very limited in what I’m able to do, like I can’t really do a maceration bucket or simmer or anything (I have to keep all stink to a minimum and outside on our tiny patio, and I don’t really want to buy any additional equipment like a bucket heater as the batch I have going are probably the last bones I’m going to do). I tried to pull it off with tweezers while it was still wet from the acetone, but it just shredded and wouldn’t come away from the bone at all, plus some of it is inside the cranial cavity where I’m struggling to get to it.

    I volunteer at a place that has a pretty bad ant problem, and I’m wondering if I put the skull out with the ants for awhile, do you think they’d go for that tissue still, or will the acetone bath have made it no longer appealing? Or is there a better way to clean that remaining tissue that I’m not thinking of?

    • Hey Mac,

      I’m glad the guide is still proving useful for you! Acetone dehydrates tissues, so that’s probably why you’re having a hard time with removing the fleshy bits. Giving the skull a quick soak in some warm water or with a little ammonia added to it will loosen that flesh right up. If you can’t remove it manually after that then you can absolutely go the any method, and I think they’ll be able to help you out

  • Thanks for your goldmine of a blog!

    I’ve got a deer skull that I’ve macerated and decreased. I did one round of whitening, and noticed that the food stuck deep down in the crevices of the teeth are preventing the teeth from looking white. I got a lot of the stuff out with a sewing needle, but there are still some unreachable bits. Do you have any tips on removing such bits?

    • Hey Hans,

      I’d recommend trying canned air or strong water pressure (a water pick like people with braces use, maybe?)

      Hope this helps!

  • The water pick worked pretty well! It got enough stuff out that the teeth now look white in profile. I would recommend that anyone else using a waterpick use a clear tote to contain the spray. It didn’t occur to me until too late that deer teeth are perfectly shaped to shoot water directly back the way it came. ?

  • Thank you for your guides! Before I found your site, I attempted to degrease some equid bones by soaking them in cold soap and water (24hrs x 2) and soaked them in diluted hydrogen peroxide (24hrs) to sanitize. There are still grease spots on some of them, but I’m not sure I can degrease them again. Cracks are forming on the shafts of all the long bones. I don’t know how old these bones have been sitting (found in storage of an old collection) and they were already partially de-greased. Any other ideas why they may have cracked and how I can prevent it in future? Anything I can do for the still greasy parts? Would super glue or epoxy be the better choice for mending long bone cracks? These are for a long-term reference collection. Thanks for any advice!

    • Hi!

      Cracked bones *usually* are caused by very low humidity or too much sun exposure, but can also be the result of the marrow expanding if they were boiled (don’t recommend.)

      Continuing to degrease (with dish soap, ammonia, or acetone) shouldn’t make the cracks any worse, and once they’re completely clean and dry you can reinforce the bones by dipping them in a solution of paraloid B-72 or Elmer’s glue mixed with water.

      Hope this helps!

      • Karina
        1 year ago

        Hello! Thank you so much, this does help a lot. They’ve been stored near a window for a few months in a room that likely does have low humidity, so I can certainly see this contributing. Do you prefer dipping the whole bone in Paraloid B-72 over painting it on or just filling the cracks with it?

        • If you have space to dip the whole bone I would do it that way, as you can make the paraloid very thin and it’ll soak in really well. You can do more dips if you’d like, and you can also wipe down the outside of the bone with clean acetone to remove the shine from the paraloid if you’d like, as it can make it look/feel like plastic

  • Pasquale
    1 year ago

    Hello Dalton
    I have an old grizzly skull that has been boiled
    Very greasy,
    Can I still use the Down method at 115F and how much ammonia I should ad to spend up the process
    I can only get a low % ammonia
    And how often I should change the water
    Thank you for the help

  • Very informative, will save link for future questions. Thank you

  • Ahoy! I’m working on a deer skull that has antlers (that I’d like to keep the original color on and don’t want to whiten). It’s totally macerated and mostly degreased, but I’m having some trouble with a patch above each eye.

    I’ve been using the clear Dawn in heated water method – keeping the temp about 120F with a bucket heater. I change the water about once a week, and use about 1/3 cup of soap per change. It’s been several about 9 weeks of this. I’m not quite sure what to do at this point. I’ve considered trying acetone (like I usually do), but I don’t want to strip the antlers of their color, and I’ve considered ammonia (but I don’t want to make the antlers brittle). Do you have any ideas about what I should do?

    Thanks (again and for everything),

    • Hey! I’d give it a whitening bath in peroxide (keep it off the antlers) and see if that helps loosen up the stubborn grease for you to finish getting it out with dawn. Also let the skull fully dry and see is the grease is still visible, sometimes wet bone just looks like grease

  • Hello Dalton!

    I’ve got a young raccoon skull that I found in front of a den in a forest. The skull was quite dirty (dirt was packed into every hole in the skull) and there were roots growing through the eye sockets. It looked like a very clean skull (no soft tissue anywhere), so I brought it home, gave it a scrub with a toothbrush and some dawn, and immediately put it into a peroxide bath for 24hrs. Note – this is the first time ive ever tried to clean and whiten a bone.

    I found out the next day that you’re supposed to de-grease a bone first before whitening it (and I noticed a small patch of the skull was a little whiter after the peroxide bath), so I pulled it out of the peroxide bath and put it into a bath of warm water with dawn dish soap. I regularly changed out the water to keep it warm (and mixed in more dish soap), but after about 3 days of de-greasing, the skull’s coloration hasn’t changed at all, and the teeth are starting to get a little loose.

    I currently have it in another peroxide bath. I’m a little confused on whether the skull needs any more de-greasing, or if it needed de-greasing in the first place; and where to go from here. Any advice would be much appreciated, thank you!

    • Hey Sam,

      Congrats on trying to clean your first skull! You can finish whitening it and then let it fully dry to see if you see any grease. It’ll be yellow or translucent looking. There’s no harm in degreasing or whitening as many times as necessary until the skull is fully clean. You can keep bouncing between the two steps as much as needed.

      The teeth are getting loose because the tissue that’s holding them in is starting to break down (this is normal and proves you’re cleaning the skull), you can glue them back in once it’s clean and dry

      Degreasing usually takes a couple months, so don’t get discouraged if you don’t see immediate results. Younger animals usually have less grease in their bones, so your skull might finish up sooner

      Best of luck! -Dalton

Trackbacks & Pings

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.