The stuff from the Bearpaw formation no one talks about

[LabRatKing]

19 hours ago, FranzBernhard said:

This is quite unusual for fossil wood, isn´t it?

Possibilities:

- It has gone through a wildfire of unspecified temperature.

- It is partly replaced by calcite, which has been partly dissolved. Did you do an acid test?

Franz Bernhard

This specimen is unlike any other fossil wood in my collection.

Acid tests were inconclusive so far. The structure helps it resist liquids, however there appears to be a positive for calcium carbonate when pulverized.

[LabRatKing]

The long weekend's testing prove inconclusive. I currently have samples prepped for microscopy...will post later today when I figure out how to transfer the microphotographs off the 'scope and to my phone without a loss of resolution, I'll post some very very interesting finds.

[LabRatKing]

UPDATE-

 

had some sample prep issues for microscopy. the voids got filled in my grit from cutting and polishing, so a i have a few samples going through the proper resin embedding to ensure clean sectioning. Bad news is this will take at least a week as I have never tried this with rock before....so I'm testing five different types of embedding resin to find which works best. My highest hopes are for the crystal clear stuff I use with my research worms.

[Norki]

Really interested to see the results of this, especially if it's reasonable to expect that you'll get a similar level of detail as the wood described in that report by Caldwell. Are you using essentially the same method that's described in the excerpt I posted?

[LabRatKing]

15 minutes ago, Norki said:

Really interested to see the results of this, especially if it's reasonable to expect that you'll get a similar level of detail as the wood described in that report by Caldwell. Are you using essentially the same method that's described in the excerpt I posted?

The specimen I have is much more mineralized so microtome sectioning is not an option without destroying both specimens and very expensive blades. Celloidin doesn't work very well on hard stuff, so I have opted for five different epoxies, ranging from JB Weld Clear Weld from the hardware store to Araldite to Epon 812 for SEM microscopy. Additionally, I have to use temperature control and vacuum to ensure proper penetration and minimize gas inclusions. I also have some fiberoptic termination equipment at my disposal, so I am giving that a try too as the polishing equipment makes it an easy process. 

 

It is a slow process as I have found in the past "off the shelf" embedding techniques rarely work as described. Right now, Ironically, the proprietary mix I use for my really tiny platyhelminths is showing the greatest promise and has the added advantage of being able to remove the resin via solvent bath shortly after sectioning and polishing, thus providing a true, unobscured view.

 

For sectioning- don't laugh too hard- a Dremel with a 545 diamond wheel has proved excellent since I can polish the sections via the 3M Duplex 6851-E (with a minor MacGuyver change to the holding arm). I have manage to create samples 1.5 x 1.5mm at a thickness of 0.26mm...and I am "polishing" that technique so I may be able to halve that dimension. I also rigged a drip system with an old 50cc chromatography tube that gravity feeds a mix of RODI/methanol/glycerin that both cools and washes away waste from polishing.

 

I really wish our SEM wasn't on the fritz and in need of a tech visit to the tune of $12k as I could really get into these samples with next to zero prep and have images in a few minutes. However, I actually enjoy light microscopy more as there is a art to sample prep.

 

I'll post up some of the current, unacceptable by my standards images shortly.

[LabRatKing]

I should add before I forget that the magnificent orange spectra is the result mostly of the presence of a surprisingly high proliferation of microcrystals of iron(II) sulfide which you will see when the pictures from the stereoscope are ready to load, and an as of yet unidentified organic compound (that as expected is very closely related to certain raw petroleum products). My biochemist is a plant guy...but his plants haven't normally been dead for this long...

 

We are still analyzing the results from initial FTIR which is a bit out of my area of expertise....spectra on that thing are all just squiggly lines to me...

 

I also have a few of my minions testing different demineralization mixtures....which is great as they were complaining about how boring worm research can get....

 

@Norki Do you guys see a lot of pyrites conspecific with your finds up there?

[Norki]

23 minutes ago, LabRatKing said:

@Norki Do you guys see a lot of pyrites conspecific with your finds up there?

Not especially, unless I'm just bad at identifying them. The sandstones that the lignitic wood is typically found in usually have lots of iron staining though, and sometimes the mollusc inclusions have an orange, druzy crust that might be pyrite.

 

I don't have any samples on hand right now, so I'm mostly going off of memory here.

[LabRatKing]

1 minute ago, Norki said:

Not especially, unless I'm just bad at identifying them. The sandstones that the lignitic wood is typically found in usually have lots of iron staining though, and sometimes the mollusc inclusions have an orange, druzy crust that might be pyrite.

 

I don't have any samples on hand right now, so I'm mostly going off of memory here.

That actually is what I had hoped you would say. Here you go- images of the microdruzy (is that a thing? is now...) pyrites.

bright yellow has been flame treated, greenish mettallic is unheated:

[LabRatKing]

And here are some more shots- quality not the best as the source pics are 3600ish x 3600ish resolution. (If you are a pro and would like access to the originals, pm me your professional email and I'll send you a link via mine)

 

These are at 30x to 50x on a Swift stereoscope taken with a Swift 18MP CMOS:

 

Here is a raw, unprocessed sample at 35x

 

[LabRatKing]

Here is the exterior "crust" at about the same:

 

Interesting that the weathered surface shows it is just that, and not an encrustation as we all thought. For lack of a better term, the exposed surfaces are "bleached"

[LabRatKing]

And here is that bit of heat treated with the torch from the previous posts (right side,gray):

 

[LabRatKing]

I cannot wait to get some better quality photos from processed samples. As you can see, the raw stuff makes the camera strain....they look much better with the ol' eyeballs.