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I’ve been interested in biogenic influences on minerals for a while. I have a large collection of stromatolites/oncolites/microbial mats etc. where algae influenced the minerals. I also have hot spring and cave minerals that were also influenced by biogenic processes. However, a new book, shown below has opened up a whole new class of Biominerals mostly influenced by nano bacteria. A lot of the theories in this book are at the forefront of science and are not yet mainstream or even accepted in some cases. However, I thought it was definitely worth a few posts here on TFF. Marco Campos-Venuti 2022 Biominerals microbial life in Agates and other Minerals (526 pages): I’ll start with some biogenic influence examples in agate. The below figure is from the book. Note although the figure talks about agate, a lot of the examples are really in jasper and not agate. Campos-Venuti goes into detail about the processes that lead to these geometries but I don’t want to get too wonky for this post. Below are a few specimens from my collection which demonstrate each of the five geometries of bacteria colonies from the figure. My friend who told me about this book warned me that if I bought the book, I would most likely be buying a lot more, different specimens. He was definitely right. 1. Laminated (truthfully I find this the hardest of the geometries to really distinguish in a piece) I have a number of pieces of Lavic Siding Jasper. Pictures of one are shown below (Note I still have to sand and polish this piece.) You can see a brecciated laminated structure. : Lavic Siding Jasper slab, Mojave Desert, California (186 grams 5.75x4x.25 inches) 2. Dendritic (Dendrites are really easy to see in minerals, although not all dendrites are from biogenic influences) I have lots of dendritic examples in minerals. A lot of dendrites are not biogenically influenced but the result of crystallization. So to be sure, I’m using a specific type of material that is from an area that Campos-Venuti specially uses as an example in his book. Sonora Dendritic Jasper slab, Mexico (136 grams 4.125x3x.31 inches). 3. Lumpy or reniform Campos-Venuti hasn’t really identified many examples of this geometry. I have two different pieces of King Cobra Jasper from India shown below. King Cobra Jasper Slab India (180 grams 7x3.25 inches 7mm thick): King Cobra Orbicular Jasper Slab, India (208 grams 4.5x4.75 inches x5.7mm): 4. Flame There are a lot of really nice examples of biogenic flame influences. Below are two difference pieces from Mexico. Flame Agate end cut, Mexico (335 grams 4X2X2 inches): Flame Agate Slab, Chihuahua, Mexico (668 grams 5.75x2.25x2.625 inches): 5. Plume There are a lot of really nice examples of biogenic plume influences. Below are two different small pieces from Oregon. NorthRidge Plume Agate Slab, Owyhee Mountains, near Homedale, Eastern Oregon (27 grams 2.25x1.5x.125 inches): NorthRidge Plume Agate Slab, Owyhee Mountains, near Homedale, Eastern Oregon (22 grams 2.25x1.45x.125 inches) I hope this post may have increased both an understanding of biominerals, biogenically influenced minerals, and an interest in them. Marco Sr.

Going through my bucket of unknowns and no better way to describe this. Found in creek with mix of Cretateous and alluvial deposits. Originally thought it was wood, not so sure now, I've never seen these spots before that look like they're floating. So tiny hard to get clear pics of the white spots that look like a flower opening and some of the spots appear to be holes at the surface. Must be biological in nature I'm thinking but what? It's pretty whatever it is.

I was taught that this is jasper. Ouachita river, central Arkansas. But could this also be like petrified wood jasper? Is there such a thing and am I far from identifying this correctly? Your knowledge is greatly appreciated.unlike other similar jasper I have found, this has a golden sheen. (?)

Crinoid calyx or echinoid? Found in gravel with Ordovician-Devonian fossils. About 2cm across at the widest point. Druzy coating over the fossil which seems to be an external mould. In orange jasper. Thanks so much!

I found this piece while walking along a building in Northern Germany...first I thought, "Huh?...this looks out of place"...I thought it was just a weather-worn veiny stone...Then I picked it up, saw the fractures and thought, "Wow!, what a nice piece of Chert or Chalcadony (va. Jasper) what are you doing here?"...The fractures are heavily weather-worn, conchoidial, opaque and with a dull luster... After a while I began thinking that the shape, weathering and banding/striping was a bit unusual (mostly opinion at the time)...I wondered if it might be a fossil...a big Brach maybe? Photos courtesy of the Google ...unlikely After seeing close-ups while cropping the pics to post here, I thought, "Hmmm...I got wood?"... It kinda looks like petrified bark to me now, but its "grainy or veiny" on both sides, which seems strange, to me, for a piece of bark... Probably purely geologic combined with wishful thinking...it happens...although, if it is geology, it would be cool to come across a Genisis Jasper where it should not be Photos courtesy of the Google ...ooops...doin' it again...sry Anyway, either way its a beautiful specimen with an interesting story... Any ideas or opinions?...thoughts will be greatly appreciated...thanks in advance... Have a nice day

Found in Michigan LP. Devonian age probably? Loads of corals and other agatized fossils wash up on that beach. This is the only one I’ve found like this.

Found this in the ‘Golden Gravel’ in our garden. Source unknown as it was here when we moved in and rock ID’d (using an app) as Yellow Jasper. The closest thing I’ve been able to find for the fossil is Hamulina or Toxoceras (last image), but not been able to find any mention of this being found in Jasper. Any ideas?

I've noticed that despite finding loads of petrified wood deep in East Texas (around Jasper, just east of Lake Sam Rayburn), I've never heard of any vertebrate material being uncovered in the area. I specifically spend a lot of time hunting petrified wood on the catahoula formation ( which is Oligocene) when I'm there, and there's definitely no shortage of said petrified wood. If so many trees are fossilized, shouldn't there be fossils of the animals that lived along side them too?

Hello TFF, I purchased this relatively inexpensive specimen at Mineralfest this past fall, and I was wondering if anyone could tell me more about it. The seller informed me it could possibly be from Madagascar, but was transparent in admitting that she couldn't confirm for sure. It was with other pieces of petrified wood that were brown, but I was drawn to this one due to the red hues. I think it's agatized, and it looks "glassy," although there are too many impurities to shine a cell phone light through it. One side is polished, and I put water on the rougher backside to show more of the details in the coloration. When I went to research the process of identifying tree species from petrified wood, I came across high powered microscopes that could identify structures on a cellular level. I don't have access to that sort of technology, but I was wondering if anyone has any guesses as to what the species could be, how old it might be, what it might be made of, or any other information that could be gathered from looking at the specimen. I'm always curious about what the prehistoric "story" could be behind a fossil, or anything related to the unique biology of ancient life. Thank you for your time, and your knowledge is greatly appreciated!

I keep running across this rock or mineral not sure what it is. Number one has a miniature cavity/geode.

Hello everyone, I found this in Washington State, Pleistocene, near Mason County. Suggestive piece of jasper or fossil bone? And I apologize for not using metric. I couldn't find my other measurer... Your thoughts would be appreciated. Chris

I am not sure what it is. Maybe Stromatolite? Dense piece. The coloration looks like it with the red.

A few more samples from another area near Fallon, NV I believe is Petrified Wood or other? Thank you.

Yesterday, I visited the famous Moenkopi Dinosaur Tracks site. The lady to guided me pointed out shiny rocks, which she said were jasper fossil corals. She let me collect them while I was being guided. I'm sure the pieces are jasper, but I'm not sure of they're pieces of coral. Are they? In addition, there were some other things she pointed out, such as dinosaur eggs, skulls, coprolites, and vertebrae. I already knew these were suggestively shaped pieces of sandstone. I'm sure this misinformation wasn't on purpose, though.

I was in an agate field in South Dakota just south of Badlands Park. Cretaceous era. I collected a few not-so-special agates and some jasper, and the pictured rock, which I thought was wind polished jasper- but it broke and had what looks to be brachiopods inside. I assume this is sedimentary or metamorphic. What is the relation between the agates in this region and the kind of specimen here? Why are there so many agate fields in this area of S Dak?

I found this on a beach on Puget Sound the other day. The parallel grain caught my eye as possibly petrified wood, but there are tons of various jaspers and agates and such on the beaches here, so it's hard to be sure. I took photos from a couple angles after I'd sanded a couple faces lightly with sandpaper. Thoughts?

I'm here to learn, explore more of the science that fuels my passion and my art, amongst friendly souls. Came to this world by blood; my dad was a geologist and outdoorsman till his passing; he remains my hero, everything I know and all my interest is born of his legacy. In my work I try to find good, reliable sources for information and materials and trustworthy individuals in their respective fields. I've read the rules of the community, I'm not here to promote, buy or sell. Just to learn. I MAY talk about what I do because it's my passion, but I'm a pretty low on the totem pole in knowledge, still, so I'm more likely to be willing to ask the goofy question, than grandstand. :-) Appreciate this forum for what it is and will treat it with respect. Lauryn

A few months ago, I traveled to Jasper, Texas for a family event. On the drive home, I took a side road about fifteen minutes North of Jasper and found a creek that looked interesting. The creek was flowing well, and there was a lot of material in the creek bed with water rushing over it. The attached pictures show specimens that I collected from the creek that day. From the locale and appearance, I had thought these to be Palmoxylon. However, in looking at numerous online images, I wasn’t able to find any petrified palm that looked quite like these samples. I’m thinking that this may just be due to these specimens being extremely weathered, but I’m not sure. I would appreciate identification assistance from those of you with more knowledge in this area. Thanks! Specimen 1: Specimen 2: I've run out of room for pictures in this post, so I'll add one more with an additional view of specimen 2.

Just returned from the wonderful country of Costa Rica. The trip was to celebrate my grandmothers 80th birthday! Being this was a family trip, I had limited time for any "back country" explorations, missing too many suppers would not have gone over well!! So I decided I would take day trips to as many beaches as possible, and consider all info collected for a future trip if anything really caught my eye. We were staying in a villa in Manuel Antone. I walked the local beaches all the way up to Quepos and paid special attention to low tide coral that would trap anything washed up. The current runs north there, so I focused on areas where the land hooked outward to catch the most debris. Beautiful sea shells, mullusks with opalesque interiors and coral were aplenty, but that is not what I was after. After 2 days and a good burn all I found fossil wise was what looks to me like horned coral encapsuled in a light green limestone. I also came across some small chunks of agate that I will have to cut n polish at a later date. I felt I had exhausted my search, and had little reason to believe these finds were deposited by any nearby rivers. So I took a bus ride south down to a little surfing village called Dominical. The beach was all tumbled river rock and driftwood. I had lost my boots on a prior drunken evening and was stuck wearing my girlfriends pink walmart beach shoes... Brutal on the feet!!! I rented a surfboard as the waves were pretty nice, and there was plenty of room in the line up to partake. My cash was in a ziplock bag which I brought out surfing, but due to thieves, I had to bury my cigs and lighter under some rocks, and used some driftwood as directionals to find in the future. While squirreling away my possessions I dropped a piece of burnt driftwood on my rock pile to help cover my stash when I noticed something... The sound was all wrong!! There was no thud, but a high pitched clack!!!! Sure enough, I had myself a piece of petrified wood!! I surfed to my hearts content, and decided to do some investigating. There was more pet wood, not in abundance, but enough to think the source was nearby! When it began to rain I noticed jasper nodules too. I showed the wood to a vendor who was working on a wire wrap necklace. He said its from the river to the south!! This led to 2 fundamental problems, 1- lack of time, 2- a good potential for crocodiles! I had seen my fill of crocs there already, some locals would feed them chickens for tips from tourists... They are quick!!!! They are mean!!! And I'm in their house!! I decided I will have to return in the future for a surfing/digging trip. I have a local guide set up for the river, he wants the wood for jewlery. I promised to teach him how to set up cheap lap saw/ polishing units so he didn't have to pay someone else for cutting his jewlery. Airfare is cheap after the new year. I'll pick up on this thread later!!!

Haven't had much to post in several months, with the Florida river levels what they usually are this time of year. Did get to the Santa Fe for a couple trips during a September draw down, but that was it. The summer, when water is high, is when I take silver smithing classes at William Holland School in Young Harris, GA. Being a 9 hour drive, I like to break it up with a stop each way to do a little hunting. I've just finished polishing the first batch of Mary Hills Jasper from Kingston, GA and am pleased with the colors. This material tends to be extensively fractured, but I slabbed a bunch of it to see if I can get some cabbing material. It takes a decent polish, with a little patience. I also stopped for more agatized coral geodes on the way up and back. The return trip was a shorter one, with a goal of getting some filming in for a potential fossil hunting television series targeted to our local PBS station. This is one of the nicer geodes I've finished polishing. I haven't seen the footage for the show yet. The goal is 2- 1/2 hour pilots for review by the station, then, if accepted, trips by a group of amateurs to various sites for each show. Waters on the way down. Will be to the Santa Fe this week and the Peace the week after.

Got some samples of things you can find in the ever-shrinking Neosho river banks. Is that a crab and tooth concretion? And what's the impression of? Can anyone help with ID on the rocks too?