How to proceed with Mazon Nodules

[Eric L]

Hi All,

I picked up a lot of Mazon Creek nodules recently. Tried the freeze/thaw technique and have probably gone through at least 10 or 12 cycles with that. Nothing has popped open but flakes continue to come off of the outside of the nodules. On 1 of the small nodules (1.5 in x .75 inch) enough pieces have flaked off on one end to show what looks like a plant fossil, maybe a fern type plant. Looks like it runs the entire length of the nodule. Is there something else I should try to get this cleaned up or just continue the freeze thaw thing?

 

Thanks

Eric

[ynot]

I have heard of freeze thaw taking many more cycles, up to 100 or more.

Lets see what @Nimravis thinks.

[Nimravis]

Where did you get these from? The pic you posted looks a little funky for a Mazon Creek concretion. Now I am not saying that it is not, it could just be the pic, but it does look odd. Any chance of posting the pic of the one that shows a possible fern?

 

As far as opening, the preferred method is Freeze / Thaw, and I would continue with that method. I on the other hand use a hammer to open the vast majority of my concretions, but I have thousands to go through, so it is the most efficient for me. With that said, I do have concretions off to the side that I will be freezing over the winter.

 

Good luck.

[Eric L]

The first pic shows the fern like object. 2nd pic is circled in yellow and 3rd is my terrible tracing job....

[Wrangellian]

The one batch I tried freeze-thawing I had the same problem as you - all the rinds flaked off (but I found nothing so it doesn't matter). After that experience, and having seen so many attractive cleanly-split Mazon nodules with rinds intact, I would be tempted to try the hammer method as Nimravis is doing. I would think the plane of weakness in a nodule would tend to be along the fossil if there is a fossil in it, so the results shouldn't be too different, and the hammer-split fossils look just as good to me as the freezer-split ones (I expect someone will tell me if I'm wrong). Just be sure to keep track of all the pieces in case the split is not so clean and you end up with a fossil jigsaw puzzle!

I found that, after so many cycles, I lost patience and tried to split the remaining unsplit ones with hammer/chisel, but found that it is not so easy to split that way after all those flakes had come off either side, leaving the edges sharp (not unlike a knapped arrowhead) - you need a somewhat blunt edge for your hammer or chisel to dig into.

[caldigger]

The first batch I did several years ago had that "onion skin" problem. I later found out it was because I had not soaked them long enough.

Soak at least several days prior to freezing to assure getting the water moisture deep inside the nodule.

I think they peel because the water is only superficially getting into the outer layers and breaking off the rinds only.

[Wrangellian]

I think I DID soak mine for several days, and they still peeled!

[Nimravis]

Eric, the concretion that you posted does appear to contain a poorly preserved fern, but it also shows that it is on the outer portion of the concretion. This type of concretion is difficult to try and crack open with a hammer. Good luck with whatever method you use and post a pic of it later.

[Eric L]

well i guess i wil keep trying the freeze method. at least for a few more times but that hammer is looking might good!

 

wonder if anyone has tried a tiny jewelers saw to kind of give it a head start. just a small cut on the side in the middle?

 

Thanks All

Eric

[Nimravis]

On 9/15/2018 at 2:06 PM, Eric L said:

wonder if anyone has tried a tiny jewelers saw to kind of give it a head start. just a small cut on the side in the middle?

Don’t do that Eric.