Bev Posted June 9, 2014 Author Share Posted June 9, 2014 The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 (edited) What is this holey rock? Edited June 9, 2014 by Bev The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 maybe another big rough agate Stewartville member of the Galena Formation rocks - good for hens and chicks, note fossil one top ??? The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 These quartz drusys are my favorite as they sparkle in the sun. I bought these 3 for $100! They even have some fossils in them. The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 3rd drusy And then we go into what started this whole obsession. Auspex calls it the "Bev Formation". It is a retaining wall that is a combination of lain rock and dragon's tooth style. All is fossilized and Auspex said more would come out and every year after winter I have more fossils!!! The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 One set of steps with the walkway that you saw pics of the rocks in. another set of steps with two new fossils this spring. This "creek bed" is all fossilized rock. The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 The Dragon's Tooth portion of the wall. Matching recepts on both sides of this rock!!! FYI that is an outdoor mechanics pit to drive on or back over and work on your vehicle. Nice small ceph on it. Macs too on it. Appeared last year. And the last one I thought you might enjoy is the Fossil Sand Box with the pond we (another thread over on Q&A) decided to name Sharks Tooth Deep - where the kids can sieve for fossil sharks teeth. Well, now you have the rest of the story! If you ever get out here, let me know. I will take you on a tour and take you hunting for your own fossils - I think Old Dead Things would say I'm okay to be around - Jim is coming back this year. LOL The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Mr_ed Posted June 9, 2014 Share Posted June 9, 2014 You do have an abundance of yard rock Bev.... thanks for posting them, some nice agates.. looks like someone went to a lot of trouble to arrange all those rocks and landscape them into the yard.. I would love to have a yard like that Cheers Ed Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 It will last longer and it actually cost less than a wooden deck that size - $2,000 complete. The creek and pond came from having to deal with gutter and down spout issues, but worked out wonderfully. I already had a 300 gallon horse tank so we just put it in place and pushed gravel and rock around it. The creek is from leftover scraps of rubber roofing and the down spout drains right into it. Overspill goes into a rain garden. And I just shop vac the pond to clean it. :-D I have a garden hose connected to the bottom to drain it in the winter. The biggest bonus was that I found a fascinating new hobby that has given me a new lease on life after having two strokes. The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Auspex Posted June 9, 2014 Share Posted June 9, 2014 Thanks for the tour of the Bev Formation "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
old dead things Posted June 9, 2014 Share Posted June 9, 2014 Yes, Bev is a great guide. I enjoyed collecting with her, but didn't allow for enough time. So this year, "if the creek don't rise" I hope to spend a few days in the wilds of MinnesOta in the fall. Jim Old Dead Things Link to comment Share on other sites More sharing options...
fossilized6s Posted June 9, 2014 Share Posted June 9, 2014 Well this is a bit late, but i managed to dig out a chert nod i had found that looks similar. I know you guys have already ruled out chert, but here you go. Cast fossils of two Rugose corals in the chert nod. And Lake Superior agate for comparison ~Charlie~ "There are those that look at things the way they are, and ask why.....i dream of things that never were, and ask why not?" ~RFK ->Get your Mosasaur print ->How to spot a fake Trilobite ->How to identify a CONCRETION from a DINOSAUR EGG Link to comment Share on other sites More sharing options...
Mr_ed Posted June 9, 2014 Share Posted June 9, 2014 It may be my imagination but the chert looks finer grained .. but you are right .. they are mighty close.. Cheers Ed Link to comment Share on other sites More sharing options...
Mr_ed Posted June 9, 2014 Share Posted June 9, 2014 A couple of Lake Superior Agates for comparison.. Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 Okay, this is probably a really dumb question... Besides banding, what is the difference between an "agatetized" rock and an "agate"? Both are formed the same way but one by chance has banding and the other not or may show eyes or slight banding. Example, I have an "agatized" brach mold that is the same color as this rock and what I believe may be agates in the rough. Also, I don't think it is fair to put up a polished or cut and polished agate as an example to compare with a rough agate. And does anyone think I should try breaking one of those rocks I think is a rough agate? And if so, how would I go about doing it? Put it in a bag and take a maul to it? Or, should I visit a person who can cut it? And, why would banded agate be more valuable than banded chert? The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
fossilized6s Posted June 9, 2014 Share Posted June 9, 2014 These are all great questions. But can only be answered by someone a lot smarter then i. I would like to know the answers also. I just know that chert is micro sediments and agates are mineralized pockets of volcanic heated rock. ~Charlie~ "There are those that look at things the way they are, and ask why.....i dream of things that never were, and ask why not?" ~RFK ->Get your Mosasaur print ->How to spot a fake Trilobite ->How to identify a CONCRETION from a DINOSAUR EGG Link to comment Share on other sites More sharing options...
Tethys Posted June 9, 2014 Share Posted June 9, 2014 Wow Bev, awesome tour of your yard. Besides banding, what is the difference between an "agatetized" rock and an "agate"? Chemically, there is very little difference as they are both silica with trace amounts of of other elements. The main difference is that agate refers to a silicate rock that formed in volcanic sediments due to hydrothermal processes. It is a primary rock that forms within voids. Agatized refers to a rock that has had its original structure replaced with silica. I have some pretty agatized banded limestone from Tennessee that has been partially replaced with pink and pale blue chalcedony. I would like to know how your teacher friend determined agate vs chert. Scratch test? SG? They do feel different in hand, with agate being in general more glassy and dense than chert. FYI for all the people who keep speculating about LSA, It cannot be both a strome and LSA due to the 500 million year gap in time between formation of LSA and evolution of stromatoporoids. Link to comment Share on other sites More sharing options...
Mr_ed Posted June 9, 2014 Share Posted June 9, 2014 (edited) Neither of those agates above are polished . As for pricing.. I think a rock shop could give you a better run down on that , but I would guess that agate sells better because it looks better and is tougher and has much better contrast between banding and non banded areas which is what gives it the edge for appearance and what gives the buyer the desire to aquire. I would buy chert , not problem if it was knapped into a nice replica artifact, but other than that it would be my guess that the agate sells better because it looks better and is tougher. Chert breaks easier and that is why it is favored for knapping. Knappers can make lovely replica artifacts from chert .. I have many of them.. can't afford all I want.. seldom see replica artifacts made from agate but I do have a few. Agate is tough compared to chert . Also when chert looks like it could be agate it is likely mistaken for agate and called agate and sold for agate. Don't ever hammer on an agate that you want to keep and be of some value. Breaking an agate with a hammer destroys it. It may well have a fracture and break in half first stroke of the hammer and not much damage done.. but more likely you will destroy it by hammering on it. I am not up on what causes the banding in agate. Mud causes the coloration in chert and jasper so I guess impurities cause the banding in agate. but that is a guess. cheers Ed Edited June 9, 2014 by Mr_ed Link to comment Share on other sites More sharing options...
Mr_ed Posted June 9, 2014 Share Posted June 9, 2014 Wow Bev, awesome tour of your yard. Chemically, there is very little difference as they are both silica with trace amounts of of other elements. The main difference is that agate refers to a silicate rock that formed in volcanic sediments due to hydrothermal processes. It is a primary rock that forms within voids. Agatized refers to a rock that has had its original structure replaced with silica. I have some pretty agatized banded limestone from Tennessee that has been partially replaced with pink and pale blue chalcedony. I would like to know how your teacher friend determined agate vs chert. Scratch test? SG? They do feel different in hand, with agate being in general more glassy and dense than chert. FYI for all the people who keep speculating about LSA, It cannot be both a strome and LSA due to the 500 million year gap in time between formation of LSA and evolution of stromatoporoids. Very good and straight forward explanation .. thanks.. I was writing my post at the same time you were I guess.. I was of the opinion that LSA is not stromatoporoid after reading about the two.. thanks.. 500 million years eh... that's not long if you are star.. Cheers Ed Link to comment Share on other sites More sharing options...
Wrangellian Posted June 9, 2014 Share Posted June 9, 2014 (edited) I don't think anyone ever said your agate/chert was a stromatoporoid! Fossilized6s' chert really does look close... I can't tell which one is finer grained but I think the chert looks more opaque, which in my mind is the best way to discriminate between them (at least via a photo). When Tethys said: agate refers to a silicate rock that formed in volcanic sediments due to hydrothermal processes. It is a primary rock that forms within voids. Agatized refers to a rock that has had its original structure replaced with silica. ... it's really the same process, the way I understand it. Agate is dissolved silica which fills voids in any host rock, such as a volcanic bubble or a fossil that has been dissolved out leaving a cavity. 'Agatized' to me refers to something that has been replaced by agate in this way. I think, as Ed said, the banding in agate comes from varying levels of impurities in the silica solution as the thing solidifies/precipitates (I assume from the outside to the center)... The bands in chert would also be the result of the layering of different compositions but in an originally sedimentary process, as limestone or shale, etc. It may have been altered by heat/pressure later but as I understand it, chert (at least the layered kind) was originally sediments. I'm not sure chert is ever altered to the point where it is nearly glassy like agate but that's why I would expect chert to be more opaque. I have many examples of each and this is the main difference I notice, but of course my agate and my chert could be different from your agate and your chert. This is why we need a real expert to sort this all out, and preferably to look at your chunk! I do see a couple pieces that look like agate in your yard... I would wait to find someone with a saw to slice them! Edited June 9, 2014 by Wrangellian Link to comment Share on other sites More sharing options...
Bev Posted June 9, 2014 Author Share Posted June 9, 2014 Squalicorax, reply #2 "Hard to say if this is a silicified stromatoporoid or banded chert.Due to the curvature and mound like shape i'd say this is a stromatoporoid." The science teacher retired from SE MN and very, very knowledgeable in this area was confidant it is agate NOT chert. The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
PRK Posted June 9, 2014 Share Posted June 9, 2014 (edited) Where is the "semantics" man?when we really need him? Edited June 9, 2014 by PRK Link to comment Share on other sites More sharing options...
Auspex Posted June 9, 2014 Share Posted June 9, 2014 ...The science teacher retired from SE MN and very, very knowledgeable in this area was confidant it is agate NOT chert. Did he mean "agate" as in the volcanic or void-fill origin, or did he mean "agatized", as in the replaced by microcrystalline quartz sense? If the former, I cannot see how it could also be a fossil stromatoporoid. It seems he meant it in the latter sense. What other fossils in your region are agatized? "There has been an alarming increase in the number of things I know nothing about." - Ashleigh Ellwood Brilliant “Try to learn something about everything and everything about something.” - Thomas Henry Huxley >Paleontology is an evolving science. >May your wonders never cease! Link to comment Share on other sites More sharing options...
Bev Posted June 10, 2014 Author Share Posted June 10, 2014 Wow, if only I had a memory... Last year I put up a brachiopod mold fossil that John K. (I believe) said was agatized. Same color and look as this agate. We are coming on evening here. Do you want me to take a pic tomorrow of the "agaztized brachiopod" mold? It's big and caused a lot of controversy at the time as the brach is most common in the Silurian which we don't have except that I found it on a beach and it could have leached out of a subterraneon cave. It's getting late... The more I learn, I realize the less I know. BluffCountryFossils.NET Fossil Adventure Blog Go to my Gallery for images of Fossil Jewelry, Sculpture & Crafts Pinned Posts: Beginner's Guide to Fossil Hunting * Geologic Formation Maps Link to comment Share on other sites More sharing options...
Mr_ed Posted June 10, 2014 Share Posted June 10, 2014 Hi Bev Bought these in san Francisco in 1971 they are chess men.. what do they look like to you.. what kind of rock? Just say what they look like to you.. I am not testing you.. just want make a point.. Cheers Ed Link to comment Share on other sites More sharing options...
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