Squidsky Posted March 25, 2018 Share Posted March 25, 2018 22 minutes ago, digit said: Nice to see that I've contributed something worthwhile. This is probably what John is referring to: http://www.thefossilforum.com/index.php?/topic/55231-mazon-creek-nodule-hoard-from-fossil-rock/ http://www.thefossilforum.com/index.php?/topic/67147-freeze-thaw-method-advise/&tab=comments#comment-706214 Cheers. -Ken Would you happen to have any tips for partially exposed nodules? Link to comment Share on other sites More sharing options...
digit Posted March 25, 2018 Share Posted March 25, 2018 The idea behind the freeze-thaw method is that water can work its way into the nodule and pop it along the plane of the fossil as that would be the weakest point. The nodules I've found at Mazon Creek have either been complete (unopened) or ones naturally weathered and "popped" by Ma Nature. Don't think I've ever tried it on one that had a partially exposed fossil. I'd say give it a try and see if you can get the remainder to separate and expose the complete fossil. Cheers. -Ken P.S.: Love the username--the password to one of my accounts back in college days was "squidlips". Link to comment Share on other sites More sharing options...
LiamL Posted June 4, 2018 Share Posted June 4, 2018 Would the freeze thaw method work for hard whitby (yorkshire) nodules? Yorkshire Coast Fossil Hunter Link to comment Share on other sites More sharing options...
digit Posted June 4, 2018 Share Posted June 4, 2018 Not familiar with those nodules so I can only guess. The Mazon Creek nodules tend to have a fossil plane which forms a bit of a weakness in the nodule. The siderite in the nodule is not particularly highly water permeable but the process of repeated freeze-thaw cycles aims to get water to seep in through micro cracks and fissures to penetrate deeper into the nodule. The mechanical pressure of the expansion during the phase transition from liquid water to ice is what is used to further weaken the nodule and promote splitting along this plane where the fossil is found within the nodule. If Whitby nodules are similar in nature then I'd expect the process may also have useful results. We know this technique works for Mazon Creek nodules because we often run into naturally split nodules due them weathering with annual freeze-thaw cycles. If you find Whitby nodules that are naturally weathered and split then I'd suggest this bodes well for this technique manually applied. If you give it a try, please report back so that others can learn of your results. Cheers. -Ken Link to comment Share on other sites More sharing options...
caldigger Posted June 4, 2018 Share Posted June 4, 2018 2 hours ago, LiamL said: Would the freeze thaw method work for hard whitby (yorkshire) nodules? I tried it on a couple that I got on a trade. Didn't do anything but create a cold rock. Then again I could barely even touch It with a strong engraver either. Link to comment Share on other sites More sharing options...
LiamL Posted June 4, 2018 Share Posted June 4, 2018 5 minutes ago, caldigger said: I tried it on a couple that I got on a trade. Didn't do anything but create a cold rock. Then again I could barely even touch It with a strong engraver either. What about a good air pen? Yorkshire Coast Fossil Hunter Link to comment Share on other sites More sharing options...
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