Freeze Thaw Cycles In Fossil Prep.

[Roz]

I just bought a few dozen of un open Mazon Creek nodules and will just place them in a pail of water on the patio and go through a series of freeze thaw cycles..... gentle approach I have got all winter for this project... bit like watching paint dry . PL

Yes, I am afraid I don't have your patience. That's why I am looking

for a quicker method. Of course if it were anything from Mazon Creek

I would be cautious for sure. I hope to go there within the next year.

I have family a couple of hours from there so next visit going to take

a detour.

[Xiphactinus]

I have tried the microwave idea myself but the matrix exploded

so couldn't tell if anything had been inside. I did nuke it too

long. I may experiment with maybe 5 seconds at a time just

as an experiment.... I am not suggesting this as a method. I

will be using just clumps of matrix.

Roz - don't nuke 'em...it won't work. The water inside will boil, turn to steam and explode. The whole concept of the freeze/thaw is that the freeze does the work, not the thaw. Speeding the thaw process does nothing. To speed the process, you need to increase the number of cycles. It's easy enough to put your nodules in just enough water to cover them and freeze. Run them under hot water until thawed, rinse, any popped open? No? Repeat....you can do this 2-3 times in a day.

Edited January 8, 2010 by Xiphactinus

[Roz]

Roz - don't nuke 'em...it won't work. The water inside will boil, turn to steam and explode. The whole concept of the freeze/thaw is that the freeze does the work, not the thaw. Speeding the thaw process does nothing. To speed the process, you need to increase the number of cycles. It's easy enough to put your nodules in just enough water to cover them and freeze. Run them under hot water until thawed, rinse, any popped open? No? Repeat....you can do this 2-3 times in a day.

OH, well I won't then. Didn't realize it was the freeze that did the work, not the thaw...

Thanks for explaining...

[PaleoPutz]

I have been doing this recently with some mazon creek nodules. I had a couple pop open after 2-3 cycles. I didn't even have to hit them with a hammer. They just pulled apart in my hands.. a couple nice little ferns.

Edit: This reminded me to go check my tub and I found another open. I didn't have to do anything to it.. It was in two pieces in the tub.

Edited January 8, 2010 by PaleoPutz

[Roz]

I have been doing this recently with some mazon creek nodules. I had a couple pop open after 2-3 cycles. I didn't even have to hit them with a hammer. They just pulled apart in my hands.. a couple nice little ferns.

Most cool, do you have pics of the ferns? Would like to see

if you get the time.

[glacialerratic]

Pleecan,

I know it's cold in Ontario, but your refrigerator freezer or a box freezer is much more effective. 48 hrs. in, then thaw. Give them some firm taps with a hammer every 4th time or so.

I just added another 200 nodules to the 3 pots I'm freezing, probably around 1,200 total. Nothing good, yet. Empty nodules, bits of worms, plenty of unidentifiable or poorly preserved stuff -- mostly from a tipple pile just west of Braceville, now closed to the public. Essex biota. Probably split around 100 so far, with around 15 freeze/thaw cycles. I seem to get lots splitting at around 20-25 cycles. Shabica's book notes that some Pit 11 nodules take 50 or more freeze cycles to split!

Good luck!

Tim

[Roz]

Michigan Tim,

Hope you post when they are opened as I am pretty sure you

will find something. There used to be a guy that owned land from the area that would take you

out there in his boat and look on his property. I have lost all contact info for him though..

[PaleoPutz]

As requested...

The one on the far left is the one that I just found open a few minutes ago. The top piece is paper thin though so that helped I'm sure. I thought the one on the right was kind of cool because it looks like there is two different ferns there. They aren't the best preserved, but I am easy to please.

[Auspex]

I smile every time I see a Mazon Creek fern nodule

There is just something soooo cool about them!

[Roz]

Thanks so much! Those are cool and the one on the far right looks like 2

fossils for sure. I am not certain the second fossil is a fern leaf though.

It almost looks like a bark piece or something. That's just me though..

Love the pup that just opened. Beautiful preservation imo.

It must be extra exciting to split something open and have it reveal

something hidden for millions of years. What a high! It hasn't happened

to me yet but still hoping.

[pleecan]

Pleecan,

I know it's cold in Ontario, but your refrigerator freezer or a box freezer is much more effective. 48 hrs. in, then thaw. Give them some firm taps with a hammer every 4th time or so.

I just added another 200 nodules to the 3 pots I'm freezing, probably around 1,200 total. Nothing good, yet. Empty nodules, bits of worms, plenty of unidentifiable or poorly preserved stuff -- mostly from a tipple pile just west of Braceville, now closed to the public. Essex biota. Probably split around 100 so far, with around 15 freeze/thaw cycles. I seem to get lots splitting at around 20-25 cycles. Shabica's book notes that some Pit 11 nodules take 50 or more freeze cycles to split!

Good luck!

Tim

Thanks for the advice Tim! Wow 1200 Mazon Creek Nodules ! Holy Smokes.... that the equivalent of $1200 worth of nodules on Ebay... with those odds ... there should be some gems in there. Please post if you find anything interesting. PL

[Terry Dactyll]

Nice fossils...... you know me , I just whack em on a good anvil, Ive lost a couple of thumb nails though so be careful....

Tim..... do you hit them whilst they are still cold from the freezer, I was wondering this as the cold may change the properties of the rock and it may become more brittle as a consequence and follow the natural plain of weakness across the fossil more easily... I would imagine severe temperature fluctuations will have some effect on the properties of rock....

[Bill]

Has anyone tried heating a nodule in a fire, then dropping it in cold water?

[pleecan]

Hi Bill: Rapid heating follow by rapid cooling will result in excessive stress build up causing the the nodule to shatter. PL

[Bill]

Hi Pl, cheers,

Yes, I realise that, but didn't mean to extremes. I just wondered if heating it to a certain temp', then cooling quickly, had been tried.

I thought that possibly, the nodule might split along the weakest plane.

EDIT: I should have added....or heating, then cooling 'relatively' quickly.

Edited January 9, 2010 by Bill

[glacialerratic]

1200 Mazon Creek Nodules ! Holy Smokes.... that the equivalent of $1200 worth of nodules on Ebay...

$1,200? ? Hmmm, maybe I should go into another line of work! I'm sure there's something good in a few of those, and it is exciting when one splits and there's something well preserved inside (nice ferns, PaleoPutz!), whatever it is.

Out of a previously split 1,200+: 2 fish, 13 nice worms, 3 shrimp, 4 sea cucumbers, 1 flying insect, many jellyfish (one is a really cool species, Lascoa mesostaurata) a bunch of bivalves (some nicely pyritized), and a bunch of plant material -- that's the good stuff -- tons of trash can stuff. I'm hoping my wife will let us purchase a new digital camera when we get our tax refund.

Yes, I realise that, but didn't mean to extremes. I just wondered if heating it to a certain temp', then cooling quickly, had been tried.

I thought that possibly, the nodule might split along the weakest plane.

Yes, what I do is take the frozen pot (an old stainless steel) and put it on our wood stove and allow the water to get hot, then tap them with a hammer. This seems to be much quicker than allowing them to thaw at room temp., followed by freezing. Sometimes I will drop a hot nodule into cold water, but haven't noticed any benefit. I have also taken nodules and placed them on the stove, getting them hot. This seems to produce multiple fracture planes, and the nodules break up into pieces when they do split, kind of like hitting them too hard with a hammer.

do you hit them whilst they are still cold from the freezer, I was wondering this as the cold may change the properties of the rock and it may become more brittle as a consequence and follow the natural plain of weakness across the fossil more easily... I would imagine severe temperature fluctuations will have some effect on the properties of rock....

I have not done that, as they are warm by the time I get my hands on them. But that's a good idea to try out -- just may help the reluctant ones. I'll give it a try over the next few weeks.

Tim

[flyguy784]

Don't know about using freeze/thaw for preping fossils. I did hear, just the other day and thought it might be interesting to some here. The "freeze" part of this results in a 10% increase in volume of the water and generates approximatly 1000 PSI of force.

[Auspex]

Has anyone tried heating a nodule in a fire, then dropping it in cold water?

With disastrous results; though it produces interesting driveway gravel...

[Bill]

Thanks for the replies, All.

[Roz]

Has anyone tried heating a nodule in a fire, then dropping it in cold water?

\\

I used to do that with clear marbles and bottles. They would make the greatest fractures designs.

Except I used the oven and cold water.

[glacialerratic]

The "freeze" part of this results in a 10% increase in volume of the water and generates approximatly 1000 PSI of force.

That is interesting. Didn't know that -- those nodules can stand up to some force! Thanks for the input.

Terry Dactyll, I think you're idea of tapping a frozen nodule, with the info given above, might work, esp. on ones that are starting to fracture, but resisting a complete splitting. I've got one of those now, and it's driving me nuts! I can see a portion of the fossil. The one tip I'd add is to make sure the nodule in question is completely water saturated (some dry ones will bubble/fizz when dropped in water) prior to freezing (Shabica's book says 48 hr. soak) perhaps followed by submerged cooling, getting the nodule as cold & wet as possible before freezing. I'll post results on the stubborn one...

Tim

[PaleoPutz]

$1,200? ? Hmmm, maybe I should go into another line of work! I'm sure there's something good in a few of those, and it is exciting when one splits and there's something well preserved inside (nice ferns, PaleoPutz!), whatever it is.

Out of a previously split 1,200+: 2 fish, 13 nice worms, 3 shrimp, 4 sea cucumbers, 1 flying insect, many jellyfish (one is a really cool species, Lascoa mesostaurata) a bunch of bivalves (some nicely pyritized), and a bunch of plant material -- that's the good stuff -- tons of trash can stuff. I'm hoping my wife will let us purchase a new digital camera when we get our tax refund.

.....

Tim

Very cool, I haven't found much fun stuff like that. They only thing that wasn't botanical was a possible worm. If you need help opening some of those, let me know...

[glacialerratic]

Very cool, I haven't found much fun stuff like that. They only thing that wasn't botanical was a possible worm. If you need help opening some of those, let me know...

Were are you hunting, PaleoPutz? I spend most of my time in the south half of Pit 11. Eagle & Monster Lake, and just to the north of the gravel road that splits the refuge.

The further north to east you go, the biota changes from Essex to Braidwood.

Go south for the Jellies!

Tim

[PaleoPutz]

Were are you hunting, PaleoPutz? I spend most of my time in the south half of Pit 11. Eagle & Monster Lake, and just to the north of the gravel road that splits the refuge.

The further north to east you go, the biota changes from Essex to Braidwood.

Go south for the Jellies!

Tim

Unfortunately, I have to buy the nodules I open. I haven't been able to take a trip to any fossil locations yet. Usually when a trip gets mentioned between the wife and I, she expects a beach and cabana boys...

[Roz]

I find a lot of nodules while hunting especially in Pennsylvanian age sites.

Almost all are fairly small so decided to start putting them in ice cube trays.