TimS Posted October 14, 2019 Share Posted October 14, 2019 This baculite piece appears to have undergone replacement by chalcedony. The walls of the empty chambers are very thin and delicate. There is a bit of original nacre intact. Thunder Basin area of NE Wyoming. 12 Link to comment Share on other sites More sharing options...
Shamalama Posted October 14, 2019 Share Posted October 14, 2019 That is a very cool piece. Did you find more in the same area? I'd be curious to see if that is a common mode of preservation in that area. -Dave __________________________________________________ Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPheeIf I'm going to drive safely, I can't do geology. - John McPheeCheck out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/ Link to comment Share on other sites More sharing options...
Fossildude19 Posted October 14, 2019 Share Posted October 14, 2019 That is extremely cool! Tim - VETERAN SHALE SPLITTER VFOTM --- APRIL - 2015 __________________________________________________ "In every walk with nature one receives far more than he seeks." John Muir ~ ~ ~ ~ ><))))( *> About Me Link to comment Share on other sites More sharing options...
Ludwigia Posted October 14, 2019 Share Posted October 14, 2019 Exceptional! Greetings from the Lake of Constance. Roger http://www.steinkern.de/ Link to comment Share on other sites More sharing options...
jpc Posted October 14, 2019 Share Posted October 14, 2019 that is a nice one. Link to comment Share on other sites More sharing options...
Pagurus Posted October 14, 2019 Share Posted October 14, 2019 2 hours ago, Shamalama said: That is a very cool piece. Did you find more in the same area? I'd be curious to see if that is a common mode of preservation in that area. What a wonderful display piece this is, with an interesting (and beautiful!) preservation. I see that Tim posted some similar specimens in an older post here on the forum. Collecting looks good out there! Start the day with a smile and get it over with. Link to comment Share on other sites More sharing options...
TimS Posted October 14, 2019 Author Share Posted October 14, 2019 4 hours ago, Shamalama said: That is a very cool piece. Did you find more in the same area? I'd be curious to see if that is a common mode of preservation in that area. As Pagurus mentioned, I have found some other pieces with chalcedony replacement, but so far this is the only piece i've seen where the chambers remained empty. The other agatized ones are solid throughout. The most common baculites in the area are just a soft muddy gray material with little detail, with the occasional cream or brown replacements with what i think are calcite and barite. The blue-gray chalcedony pieces are few and far between. There are massive shale flats in the area where you can spend all day and not see hard stone like chert / quartz etc., so it's a mystery how some pieces agatize. I also found a partially agatized limb cast near this piece which is very odd. Here are a few more from the same spot --- one filling with barite crystals, one that is partially agatized, and one that decided to grow a crystal garden on the end. 10 Link to comment Share on other sites More sharing options...
Mark Kmiecik Posted October 14, 2019 Share Posted October 14, 2019 The last one is beyond spectacular. Congratulations. An amazing combination of fossil and mineral. Just WOW! Mark. Fossil hunting is easy -- they don't run away when you shoot at them! Link to comment Share on other sites More sharing options...
Misha Posted October 14, 2019 Share Posted October 14, 2019 Those are incredible! Link to comment Share on other sites More sharing options...
minnbuckeye Posted October 14, 2019 Share Posted October 14, 2019 Most of my favorite fossils are a combo of fossil and crystallization. Those are making me drool!!!!! Mike 1 Link to comment Share on other sites More sharing options...
DPS Ammonite Posted October 14, 2019 Share Posted October 14, 2019 Amazing! Chalcedony with probably two forms of calcite. Can you show us a picture of the piece under long and short UV light? My goal is to leave no stone or fossil unturned. See my Arizona Paleontology Guide link The best single resource for Arizona paleontology anywhere. Link to comment Share on other sites More sharing options...
ricardo Posted October 14, 2019 Share Posted October 14, 2019 4 hours ago, TimS said: Some white chabazite penetration twins? 1 Link to comment Share on other sites More sharing options...
Johannes Posted October 15, 2019 Share Posted October 15, 2019 12 hours ago, ricardo said: Some white chabazite penetration twins? I'm in with chabazite and stilbite on calcedony... @TimS Hope you have the oposite part of this piece, too? Link to comment Share on other sites More sharing options...
Coco Posted October 15, 2019 Share Posted October 15, 2019 16 hours ago, TimS said: Gorgeous ! Coco ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
Shamalama Posted October 15, 2019 Share Posted October 15, 2019 18 hours ago, TimS said: Oh my, that is stunning. Definitely orange Calcite on pale tan Chalcedony, but I'm hesitant on the Chabazite ID for the white crystals. I am thinking Dolomite instead. 1 -Dave __________________________________________________ Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPheeIf I'm going to drive safely, I can't do geology. - John McPheeCheck out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/ Link to comment Share on other sites More sharing options...
Coco Posted October 15, 2019 Share Posted October 15, 2019 I think dolomite too. Coco 1 ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
erose Posted October 15, 2019 Share Posted October 15, 2019 Simply fabulous. Try hitting them with ultraviolet light as well. Link to comment Share on other sites More sharing options...
Johannes Posted October 15, 2019 Share Posted October 15, 2019 3 hours ago, Coco said: I think dolomite too. Coco Why? Link to comment Share on other sites More sharing options...
Coco Posted October 15, 2019 Share Posted October 15, 2019 Because of the slightly curved shape of the white crystals, or at least what I think I see. Coco 1 ---------------------- OUTIL POUR MESURER VOS FOSSILES : ici Ma bibliothèque PDF 1 (Poissons et sélaciens récents & fossiles) : ici Ma bibliothèque PDF 2 (Animaux vivants - sans poissons ni sélaciens) : ici Mâchoires sélaciennes récentes : ici Hétérodontiques et sélaciens : ici Oeufs sélaciens récents : ici Otolithes de poissons récents ! ici Un Greg... Link to comment Share on other sites More sharing options...
TimS Posted October 16, 2019 Author Share Posted October 16, 2019 I'm not certain what the crystals are on the last piece, keep getting different opinions from the visual ID. Dolomite and chabazite hadn't been suggested. I've never heard of chabazite before but I'm not ruling anything out and thanks for the ID help. I'm hoping to take it to the SD School of Mines where they host a public rock ID day in January for a first-hand opinion to add to the list. Here's a pic using my only UV, a $5 flashlight. To my eye the orange crystal fluoresces bright orange, and the white crystals don't fluoresce. My phone sees it differently. I'm going to a rock show in a couple weeks and am sure someone there will have a good UV I can check it with. 3 Link to comment Share on other sites More sharing options...
Johannes Posted October 16, 2019 Share Posted October 16, 2019 Would be nice if you share the information you get there! Btw., if you put an uv-band-pass-filter directly before the uv-light/LED (which cover often a broad bandwidth of wavelength, including visible blue and violet light), you taking out the visible light and get the real fluorescense colours of the minerals, even when fluorescense is not so strong... edit: should be looking a little bit more like this (slight fluorescence in the orange mineral and a little stronger in the white cubes): 1 Link to comment Share on other sites More sharing options...
Shamalama Posted October 16, 2019 Share Posted October 16, 2019 20 hours ago, Coco said: Because of the slightly curved shape of the white crystals, or at least what I think I see. Coco My thoughts exactly, as well as the general diagenic nature of shales vs. volcanics in the formation of Zeolite minerals. 2 -Dave __________________________________________________ Geologists on the whole are inconsistent drivers. When a roadcut presents itself, they tend to lurch and weave. To them, the roadcut is a portal, a fragment of a regional story, a proscenium arch that leads their imaginations into the earth and through the surrounding terrain. - John McPheeIf I'm going to drive safely, I can't do geology. - John McPheeCheck out my Blog for more fossils I've found: http://viewsofthemahantango.blogspot.com/ Link to comment Share on other sites More sharing options...
doushantuo Posted October 16, 2019 Share Posted October 16, 2019 The minerals might be laumontite,heulandite or clinoptilolite. Edit hours later:the white crystals MIGHT be sucrosic dolomite 2 Link to comment Share on other sites More sharing options...
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