Apr 6, 2016 · Chert, flint, jasper and agate are all very similar (cryptocrystalline quartz), and all I know about telling them apart is that a sample is considered agate if it has a significant amount of clear chalcedony in it, flint if it's associated with chalk, and jasper if it has colorful patterns with little chalcedony.

Feb 27, 2019 · Your oolitic limestone IS biological in origin. The oolitic chert of the Gatesburg Formation is considered a chemical sedimentary formation. Several papers have been written and our mineral club has had presentations on this. I'll see if I can dig up the info. Here's a pic of an almost volleyball sized chunk of oolitic chert.

Sep 24, 2017 · Oolitic Chert. chert; gatesburg formation; white; By sTamprockcoin September 24, 2017 in Rocks & Minerals ...

Sep 1, 2024 · Their description of chert in the Oneota agrees with my own; there is an abundance of oolitic chert, as well as other oolites. They refer to bands of chert some meters thick - that's new to my info, and I wanna see them. :-)

Aug 10, 2013 · There are a number of nodules and layers of chert in this formation that preserve the original sedimentary structures before it was converted to dolostone. So if your rock is chert it is Ordovician, if it is limestone, it is Missippian. I have collected some of the Cotter/Jeff City oolitic chert. Some of it is quite pretty! PS.

Oct 15, 2018 · I discovered, after some excitement, oolitic dolomite; oolitic chert, oolitic dolomitic marble, and fossils everywhere. The marble suddenly appeared after a 6" downpour that resulted in a flood which cut my streambed as much as 3 feet deeper.

Apr 11, 2018 · I found this 40 lb chunk of what looks to be oolitic chert with some agate tubes running through it in east-central Minnesota while out agate hunting. Maybe it's considered a cold water agate, but I'm not really sure what that truly means anyways. Either way, I was wondering if there is something...

Sep 1, 2024 · DPS Ammonite - many thanks all around- the article link is greatly appreciated; that one had never surfaced for me. Their description of chert in the Oneota agrees with my own; there is an abundance of oolitic chert, as well as other oolites. They refer to bands of chert some meters thick- that's new to my info, and I wanna see them. :-)

Mar 2, 2025 · Could it be silicified oolitic limestone? ... A chert concretion formed in oolitic limestone. 1 1 ...

Apr 9, 2015 · Hi Everyone. We found this beauty in our garden along with lots of gorgeous agates and other fossils. Near antigo wisconsin. I made a few cuts with our lapidary setup. Thought it would be coral or palm