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Make Your Fossils Shiny (Simple Clearing & Polishing Tips)

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Some folks like fossils just as they are, but others prefer a polished look. No matter what you like, here’s the thing: taking care of your fossils is important, from the moment you find them to how you store them.

To make your fossils shiny, clean them with a toothbrush and water. Someone uses a thin coat of varnish when working with calcitic ammonites to brighten them up and use a kitchen towel or lint-free cloth to make them shiny.

Certain fossils need a bit of their matrix for support, but removing excess matrix isn’t an issue as long as you don’t overdo it. No matter what type of shining or polishing technique you may use, it’s best to test it on an already compromised piece before moving on to your complete fossil.

Some fossils need the surrounding rock, called matrix, to hold them together. It’s okay to take off extra rock, but be gentle. No matter how you plan to polish your fossil, try it out on a broken piece first so you don’t mess up the good stuff!

Here is everything you need to know about making your fossils shiny the right way, cleaning, and some polishing tips!

What Do You Use to Polish Fossils?
What Do You Use to Polish Fossils?

If you want to check out the best Dremel drills, you can find them here (Amazon link).

What Do You Use to Polish Fossils?

When polishing your fossils, use sandpaper, medium, or fine grit. It all depends on your fossil type and what polish you want to achieve. You will also need soft or dry bruises, cleaning cloths, and varnish.

Ammonite fossils work great with soft brushes and 600-grit sandpaper, 1,500-finer grit sandpaper for further polishing, and a polishing cloth to give it a shiny texture.

Regarding aquatic fossils, the 800-grit or higher sandpapers are the best to remove impurities. Opalescent fossils work well with Dremel tools and soapy water.

In general, visual appeal is what you want to achieve in your fossil polishing process, and the more details are visible, the better. Some surfaces of your fossils can easily chip away, but if you choose to polish them, you ensure their protection and a smooth surface that will be easier to clean.

Various types of abrasive papers, such as sandpaper, are used to remove scratches, depressions, or high areas from the surface of your fossil.

To achieve the best results, start with the 100-grit wet and dry sandpaper course and move up to 1,200-grit sandpaper or higher. Use circular motions, rub between five to ten minutes, and keep sanding as seen in this video:

You’ll know what details you want to keep during the 100-grit stage before going on to the higher-grit stage. Sandpaper and a polishing block should be used with hot water. Put the sandpaper on top of it and even the fossil surfaces. Keep the paper wet and rinse it often.

To get rid of dirt or grit, use water. To fix scratches made during the first leveling step, use finer sandpaper grits. You can quickly get rid of the roughness you made with the 100-grit with the 200-grit.

Repeat the sanding process, then switch to the 400-grit sandpaper, 800, and 1,200. You can go higher if you believe it’s necessary. Everything you switch to another grit level, you always have to ensure that the scratches from the previous grits are removed.

Once you’ve finished with the grit, the fossil is ready for polishing, which can be done in a variety of ways depending on the specimen and condition. In most circumstances, you can make your own polish or purchase varnish.

You’ll need water and a teaspoon of aluminum oxide polishing chemical to make your polish. You will make a paste to put on a leather pad and then rub it on the fossil until it is glossy.

Once finished, rewash the fossil in water and dry it. You can use a lint-free cloth to dry your fossils and prepare them for exhibition.

Other products for polishing fossils include vinegar, olive oil, metal polish, mineral oil, beeswax, carnauba, baking soda, and toothpaste.

TIP: Getting from raw rock to polished stone is daunting, but if you follow this process, you will get a specimen you’re proud of. Check out the guide in the article below:
How to Polish Rocks With a Dremel Drill? Follow These 4 Steps

Can You Polish Fossils With a Rock Tumbler?

Although the best and safest way to polish fossils is by hand, you can do so with other tools, such as a rock tumbler. However, many fossils are fragile and don’t work well with a tumbler.

You must choose the proper fossils for your rock tumbler and grit to achieve good results. The best fossils to tumble are those with a hardness similar to agate, and some fossils are composed of the same minerals, so you shouldn’t have any problems tumbling these types of fossils. Thus, the matrix surrounding the fossil is critical.

You can use a rotary tumble for fossils in the first stage of polishing. You will need 60/90 ungraded grit and let the fossils tumble between 18 and 21 days.

In the second stage, you will need a vibratory tumbler and 400 or 600 grit for 3 or 4 days. In the last stage, apply cerium oxide polish for three or four more days.

Some great fossil examples that can be polished with a rock tumbler include agatized fossils, such as crinoids, brachiopods, bryozoans, gastropods, and various other types of corals and agate fossils.

However, additional precautions might exist depending on which specimen you wish to try the three-step procedure mentioned earlier. Nonetheless, you can still use a rock tumbler to polish fossils.

Can You Polish Fossils With a Dremel?

Apart from tools such as a rock tumbler, you can also use a dremel to polish your fossils. A Dremel is a small rotating grinding wheel that you can use to sand and polish your fossils; however, not all fossils can be polished with a Dremel.

A Dremel works best in polishing hard and giant fossils; you shouldn’t use it on delicate or small fossils. Opalescent fossils, for example, can be polished with a Dremel machine, but it all depends on their size and shape. You can also use a dremel to polish your petrified wood specimens easily.

TIP: Our choice for polishing fossils or rocks is the Dremel 4300-5/40 kit (Amazon link) manufactured by Dremel. This tool is perfect for polishing fossils, stones, and minerals.

Just attach the sanding to your Dremel and use circular motions on your fossils using a grit sandpaper until you reach the finer grits. You can finish the sanding procedure with a felt polishing wheel to make your fossils shine or apply mineral oil or beeswax to protect your specimen further.

How Do You Clean Fossils?

How Do You Clean Fossils?
How Do You Clean Fossils?

Cleaning your fossils is one of the most important steps before moving on to the polishing procedure and achieving that shiny look. The cleaning procedures might vary depending on what type of fossil you have.

For instance, shell fossil specimens may be cleaned with heated water and a small amount of detergent. Additionally, a gentle brush will be required.

If fossils are oil-stained, bleach or gasoline may be employed to eliminate the stains. However, it is generally advised to refrain from applying these chemicals to specimens collected from soil or not petroleum-rich strata. Vinegar is also an effective method for cleaning fossils.

In certain instances, such as with ammonite specimens, it is necessary to soak them in white vinegar for several hours or overnight to sanitize them.

You may rinse the sample with warm water, position it in a baking soda bowl, and allow it to sit again overnight. Finally, rinse the specimen with warm water once more and dry it with gentle, clean cloths.

This will help you remove any unwanted debris from your fossil and help in the polishing procedure. In most cases, you can use a lint-free cloth and soapy water to remove unwanted dirt and dust. Generally, the first grit you use, the coarsest, is also part of cleaning your fossils.

TIP: Fossils are remnants of organisms that have integrated into sedimentary rock. Some of these fossils contain ancient DNA. Find out more about DNA in rocks in the article below:
Do Rocks Have DNA? I Have to Disappoint You, But..

How Do You Make Fossils Shiny?

Numerous methods exist to achieve a shiny appearance if your fossils are cleaned and polished correctly. Regardless of your technique, you can consistently alternate between them to compare results and experiment until you determine the most effective approach for your needs.

An acrylic coating can be employed to enhance the luster of your fossils. Acrylic varnish is frequently employed to provide protection and enhance the color and luster of fossils.

Mineral oils are also a great option because they dry more pleasantly than vegetable oils such as olive oil. You can also use water-soluble synthetic polymer (PVA), paraloid B-72, cyanoacrylate, or butvar.

There are plenty of other methods, but it all depends on what you want to achieve and if your fossil can withstand chemical intrusions or work better with more natural ones. 

BTW: If you are looking for the best UV light for rockhounding, find out my picks below (Amazon links):


Finding fossils is one thing; taking care of them is another. When showing off your outstanding collections to friends and family, always use the regular cleaning and polishing processes described above.

And don’t forget to apply a coating to bring out the hues and shine whenever you want to display your collection!

TIP: If you wish to drill holes in rocks, you will need the right tools and techniques to use them properly. Find out the step-by-step guide in the article below:
DIY: Drilling Holes In Rocks With & Without Dremel Drill