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Fossilized Shark Teeth on the Internet |
FOSSILIZED SHARK TEETH
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Notwithstanding the above statement, these fossils CAN be harmed by external forces. If you were to put a small tooth in a beaker of high molarity muratic (hydrochloric) acid overnight, in the morning you would likely find only the enamel "shell" left. The mineralized root and dentin would be eaten away by the acid.
Another common sense factor (that is often overlooked) is handling and/or displaying the fossil in an area that would cause minimal damage if it were dropped or knocked off the display surface.
Normal care taken when displaying, handling and cleaning fossils can help insure that you minimize the harm that you might do to them over time.
CARE IN DISPLAYING FOSSILS
Fossils can be degraded by many factors. One environmental agent that can cause long term problems is sunlight. The major injury to the fossil is "sunburn" or color fading. We have several teeth in our private collection that must have lain out with one side up for a lengthy period. The exposed side has significantly lighter color in the root and the enamel than the side that was lying on the ground. Many of the Chilean Atacama Desert teeth show this type of degradation. Whether this is desirable is a matter of personal taste.
Another factor in deciding where to display your fossil is humidity. In areas where the humidity is constantly high, such as pool side, in the bathroom or near the kitchen sink, the porous areas of the tooth will adsorb and absorb the moisture from the ambient air. Over time this water in association with other chemicals (such as carbon) can form injurious compounds (such as carbonic acid) which will deteriorate the fossil. (A large majority of caves are formed in this manner.)
CARE IN HANDLING FOSSILS
Part of the experience of "owning" a fossil is examining, admiring, fondling and showing it to others. This discussion is not meant to discourage this adoration in any way, but to minimize the impact on the fossil. There are some common sense things that you can do that will insure that the fossil is not degraded.
Shark teeth fossilize in several different ways and are subject to many varied conditions over the millions of years since they were first lost. The veteran collector knows the difference among teeth that were collected from a North Carolina riverbed, Florida potash mine, California's Sharktooth Hill or Moroccan desert. The enamel is virtually the same each one of these teeth, but the root and dentin chemical composition is different. The root "ears" of California extinct Mako teeth can easily be snapped off with little more than fingertip pressure. The "ears' of a North Carolina river teeth are virtually impossible to break in this manner.
The primary constituent of the riverbed teeth is tightly crystalline fluorapatite - Ca10(PO4)6F2, the potash mine and Sharkstooth Hill teeth are loosely crystalline calcium phosphate and the desert teeth are generally poorly mineralized calcium phosphate and calcium carbonate compounds (where the crystalline structure of the original fossilizing material has been leached out over time). [This is largely a generalization and more exact constituents can only be found by assessment of the particular sedimentary environment of the preserved/fossilized teeth. Making this task more complicated is the fact that the sedimentary environment of the teeth may not have been constant throughout their burial history. This is especially true of a "reformulated" formation such as the Hawthorn Formation.]
The bottom line is this: some teeth are inherently more susceptible to external influences than other teeth. For example, if you were foolish enough to scrape the root of a California Mako, Moroccan Otodus Obliquus or a potash mine C. megalodon across a brick, you will leave a trail of what looks similar to chalk and you will find that the root is seriously worn down. Try this same experiment with a North Carolina river tooth and the tooth will incur a lot less damage. The root material in some teeth is very porous and fragile and can be harmed by handling incorrectly. Let's try another theoretical experiment with a drop of water and a drop of machine oil on to the root of a North Carolina tooth and a Moroccan tooth. After an hour or so, the water and oil droplets on the North Carolina tooth have hardly soaked in but we find that they have almost entirely been absorbed by the Moroccan tooth.
The skin of the human hand has a host of chemicals that can possibly contaminate a fossil during handling. Even "clean" hands have a surface layer of salts, water and oils which will, in the long term, degrade the composition of the tooth and in the short term, it's appearance. Many "estate" teeth show this degradation as the top and the thickest part of the root will have a darker color than the rest of the root. This is primarily due to the deposition of skin oils in handling.
We at MegMawl recommend that the tooth be handled (especially by children) while seated on a large sofa in a room with a carpeted floor. The tip, serrations, enamel and root "ears" of any tooth can easily be broken by dropping on a hard surface. If possible, the tooth should only be handled on the enameled part of the tooth. (Even this can cause long term problems as the contaminates can penetrate the tooth through the cracks in the enamel.) Handling the fossil in this manner will minimize the impact of skin contaminates on the more porous parts of the fossil. You might even want to consider using thin gloves when handling your high grade specimens.
CLEANING FOSSILS
With normal care in handling fossils, very little in the way of cleaning is ever needed. This is not the case with fossils which are bought from some dealers who neglect to clean their product prior to selling them. In these cases, the "white stuff", "sea life" or excess matrix can be removed by a professional. (See photos below for views of a partial tooth right out of the river - #1 and after the first stage of our 7 stage cleaning process - #2.) We provide a FREE CLEANING SERVICE no matter where the fossil was bought. See "Free Cleaning Service" link on our HomePage or email us for details.
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Skin oils and salts can be removed from the enameled areas of the tooth with a clean cloth lightly saturated with alcohol (Rubbing Alcohol, not your favorite single malt scotch) and then a cloth dampened with a light solution of soapy water. Flush with clean, cold water for several minutes. Dry the fossil over a floor air-conditioning vent overnight before putting it away or placing it back in the display case.
Soaking the tooth with acetone and then carefully brushing the root surface with a soft, old toothbrush (river teeth only) will also remove the surface layer of body oils.
With a few common sense practices and proper care, your fossils will be around to astound and amaze your descendants for another 14 million years.
DISCLAIMER: MegMawL can not be held responsible for any damage or deterioration caused by following any of the above practices or procedures. This article is for information only. We recommend that fossils of any kind be cleaned only by professionals.
Copyright MegMawL © 1997. All rights reserved.