Trilobite Colouring

[Kane]

Or coloring, for my US friends who are averse to the letter 'u' here

 

As I have just begun my little journey of prep, I look to distinguishing my prepped trilobites from their matrix a bit more. I once botched a roller with wood markers, and then a sharpie - derp!

 

But I channeled the old "Nasenfett" idea to apply Murphy's oil soap that seems to both clean and later darken the trilobite after blotting it. 

 

Is that too amateur hour? Should I be investing in something better? I am looking to ensure that they pop, but will not be applying hot pink nail polish.

[caldigger]

I know many of the trilos of the Moroccan variety utilize shoe polish to make them stand out.  You may try a light coating of mineral oil on just the fossil. I have heard of floor polish being used as well. Play it like the Karate Kid, wax on...wax off.

Others may have better ideas.

I personally prefer to keep things in their natural state. Not a fan of polishing/ cutting/ or artificially coloring.

[Raggedy Man]

No information on what to use from me. I keep them as natural as possible.

[Raggedy Man]

2 hours ago, caldigger said:

I know many of the trilos of the Moroccan variety utilize shoe polish to make them stand out.  You may try a light coating of mineral oil on just the fossil. I have heard of floor polish being used as well. Play it like the Karate Kid, wax on...wax off.

Others may have better ideas.

I personally prefer to keep things in their natural state. Not a fan of polishing/ cutting/ or artificially coloring.

Shoe polish is also used to give a fossil colour appearance when crafting replicas. I figured I'd use the u in colour, in case you were confused...lol 

[Kane]

Lol, a good suggestion that I will look into, sampling with non-important specimens first.

 

As for "u" in colour, us Canucks are such etymological purists to the Latin by way of French 

[PA Fossil Finder]

Like others have already stated, I think fossils are best left in their natural state (excluding preparation, consolidation, or gluing broken pieces back together). However, I have used mineral oil on some modern seashells to keep them glossy - I'm sure you could do this with some fossils. Just don't use vegetable oil - it could turn rancid on your fossils.

[Wrangellian]

On 2016-09-09 at 6:11 PM, Kane said:

...

As for "u" in colour, us Canucks are such etymological purists to the Latin by way of French 

WE Canucks are....   (Sorry, we were talking about purism and such, couldn't help it)

 

I had a thought, untested at this point: while you're experimenting, why not try just staining it with plain old black (India) ink? Then if you need it to shine, give it a coat of something that will shine it up, like paraloid or clear acrylic or something that someone else other than myself should recommend..

The benefit of the ink is that it will give you a color contrast without the shine (I think), first, in case you find you like it that way (Shiny is bad for photography), then you have the option of shining it up or not.

 

[Kane]

5 hours ago, Wrangellian said:

WE Canucks are....   (Sorry, we were talking about purism and such, couldn't help it)

 

I had a thought, untested at this point: while you're experimenting, why not try just staining it with plain old black (India) ink? Then if you need it to shine, give it a coat of something that will shine it up, like paraloid or clear acrylic or something that someone else other than myself should recommend..

The benefit of the ink is that it will give you a color contrast without the shine (I think), first, in case you find you like it that way (Shiny is bad for photography), then you have the option of shining it up or not.

 

I'm actually quite mortified and embarrassed that I made such an obvious grammatical blunder!  I'll chalk it up to Tim Hortons colloquialism, or my attempt to speak in the SW Ontario dialect - if there is such a thing

 

I might give the ink a try, depending on specimen, and on some test pieces. As an update to applying the Murphy's oil soap, it's been a few days and the darkened colouration has remained without fading (and avoiding anything that might go rancid, such as applying an edible oil product!). It is most likely a comparable effect as using other forms of oil, such as mineral oil. A light application doesn't seem to make the trilobites seem unnatural, but lends them that slightly darkened appearance they take on when mildly wet (without the sheen of being moist). 

 

To avoid the shiny residue effect that might occur in the pleural furrows, I dab the specimen thoroughly to absorb any excess oil. I've only done this with the trilobites collected from Penn Dixie (they come out dark grey/dusty black). Some of the other trilobites collected elsewhere come out naturally in a nice and distinct chocolate brown and so need no cosmetic enhancement. However, the trilobites from black or dark brown shales, such as Pseudogygites, present a different problem for creating contrast unless the specimen is pyritized or happens to have mineralized with a faint whitish-chalk patina. In the particular case of the black shale example, the contrast may be captured simply by lighting: there's a very faint "oily rainbow" and slight sheen to the fossils found in some of the darker shales.

[Wrangellian]

I'll accept the Tim Hortons colloquialism (good name), and I'm sure there's a SW Ontario dialect though that feature is far more widespread than that...

 

I would think just the ink by itself (no oil) would give you the effect you need - contrast but no sheen. I would worry that oil will make a specimen weaker/softer and maybe more attractive to dust, but I have no experience with it so I wouldn't know. Does oil not run, soak into cracks, etc?

 

[Raggedy Man]

I'm curious Kane, but could you post a few pictures of the trilobites in question? There might be a way to make them "pop" without adding a stain, polish or oil. 

[Kane]

Sure thing! To cut down on server space, I hope you don't mind if I link to a previous post of mine: 

Pic 2 is the original colour, and pic 3 is a very light application of oil as a test (they underwent more prep, and so I later reapplied for the same effect).

[Raggedy Man]

Oh Penn Dixie trilos. After the prep on the trilos from PD, I just take a dremmel and prep around it creating a whitish area. This typically brings the trilobite out. You can also polish it without adding anything. They do take a shine fairly well without additives.

[Terracite]

Hi all,  I, too, am not a fan of added colour (but am a fan of the "u" in colour).   There is so much naturally occurring variation from different locations it seem like a good idea to try to preserve that.   One way to enhance the glossy finish on shell is light air abrasion with Sodium bicarbonate.

 

[IonRocks]

I recently, guiltily applied a thin glue to the exterior of some common brachiopods that I wanted to look wet for a display. (It also brought out the colors)

 

but I am happy with it. It will also make a good experiment to see if yellowing occurs (it's also reversible)

 

I would probably keep trilobites as is though. My trilobite display right now has a couple hard to see ones, but I found lights that make them much more visible. 

[tmaier]

I'll add that my prefgerence is to only modify a fossil in the attempt to extract more information from it. So I guess that would be dissection in some cases. I don't give much thought to the appearance of it, except that it reveal as much information as is possible. It seems to me that changing the color of anything is obscuring/modifying information, and that is objectionable to me. The fossil should "be all he can be", and not be made into something that it isn't.

But prepping is an art, and everybody has their own tastes. Mine are rather technical, rather than artistic. So arguing the points is pretty futile.

[Kane]

Thanks for everyone's input. This is a good conversation to have as it does present the kind of dilemma I'm sure others may also face. I do take the point that "au naturel" is probably best in a lot of cases, and I agree with @tmaier that modification can obscure the scientific validity of the specimen in favour of aesthetics. Fortunately (or not) I haven't yet found anything of scientific significance - all fairly common and typical fossils, and so I would be loathe to even dare attempt to prep something that was significant as I'd be more likely to trust an expert rather than my clumsy hands and suboptimal tools. At present, it seems the oil-soap doesn't "seep" and doesn't result in any dramatic colouring effect - only mildly enhances the contrast for visibility. Just one partial shade darker. I don't foresee myself using this method on anything but Penn Dixie trilobites at this point. 

[DevonianDigger]

I am wondering if a sodium dithionite solution might help with the Penn Dixie trilobites.

 

I don't have any, but I will look into it. It's been used to remove the junk and oxidization from pyrites. I'm not 100% because I haven't reached that point in my studies yet, but I believe the initial blackish finish on the trilobites is due to pyrite mineralization. If that is in fact the case, a gentle once over with a sodium dithionite/HCL solution diluted with water could possibly serve as a chemical alternative to the air abrasion which strips that first layer off almost immediately. Might keep the contrast high without having to add any type of 'finish' to it. (This would probably only work well for specimens freshly uncovered from the matrix, not so much on floaters where the initial finish has been previously weathered.)

 

I am one of those people who isn't satisfied until I have independently solved all of the world's mysteries... unfortunately I also learn by trial and error, lol. This could all be nonsense. I am always willing to be told 'no', so if anyone knows anything about this idea, don't be shy! Otherwise, I'm going to look into it further and will report!

 

Sodium dithionite link - http://botanicalcolors.com/shop/mordants/sodium-hydrosulfite/

[Fossil-Hound]

@Kane and @DevonianDigger I'm experimenting now with various polishes. What would you recommend? Have you tried sodium dithionite Jay? Please post some pictures. 

[Ptychodus04]

How did I miss this thread for so very long??

 

PVA, Butvar, or Paraloid can be used to impart a bit of contrast. They will all slightly darken most specimens and are infinitely reversible for conservation purposes.

 

They are a bit shiny but this can be removed with a very gentle brushing of acetone after several applications if the effect is undesirable.

[doushantuo]

I totally misunderstood this thread,see?

schoenTOGEOJ-8-113.pdf

[doushantuo]

[RJB]

Ive heard of using mineral oil many times before and now two more times on this thread.  Ive never used it.  My question is:  Once mineral oil is applied, does it dry?  Does it stay oily? 

 

RB

[Coco]

I can't answer you, but I use the liquid paraffin on my current shells, and I mop them with some paper of TOILETS So that doesn't remain fat later, contrary to organic oil

 

Coco