Greetings, @mike-steinhorst! I doubt it could be a “hinge of an ancient Gastropod” because this specimen would have a more concavo-convex geometry in addition to a different texture.

Great specimen, @evan-walsh!

Greetings, @mike-steinhorst! When I first saw this picture, I thought it was vesicular basalt lava, but it is difficult to tell from the angle of the photograph. Could you please provide pictures with several angles and one where we can see the entire specimen? Thank you!

Greetings, @elizabeth-henson and @samantha-ocon! I concur that this is not petrified wood; chert seems to be a reasonable possibility.

Greetings, @elizabeth-henson and @corinne-daycross! I agree that this is only an interesting rock and not a fossil, although it does not fulfill the definition of agate (which is a primarily translucent piece of cryptocrystalline silicate with banding from the incidental elements within).

Greetings, @jeff-alliaume! This appears to be Genus Cleoniceras or a similar genus, but the preservation makes it difficult to say with absolute certainty. The popularity of Cleoniceras makes this designation a good guess, however. Did you purchase this specimen or did you collect it from the field yourself?

Thank you @mackenzie-smith for your insightful comment! Although he is probably interested in this discussion, @imagallanes must be wondering how he got pulled into the conversation! 🙂 Nonetheless, I for one always find it interesting to learn more about petrified wood. Thank you again to you both for sharing!
-Isaac Pope

Greetings, @jeff-alliaume and @mackenzie-ross-2! As I noted in our previous discussion, this is another excellently preserved ammonite of genus Perisphinctes. Until we know more about the age, you can update the taxonomy to Kingdom Animalia < Phylum Mollusca < Class Cephalopoda < Order Ammonitida < Family Perisphinctidae < Genus…[Read more]

Thank you, @jeff-alliaume! Once again, excellent specimens!

Greetings @elizabeth-henson and @mackenzie-ross-2! I would say that this is petrified wood, especially as I have collected many similar pieces reworked in quaternary alluvium near Glendive, Montana. Elizabeth, isn’t this the same specimen (https://www.myfossil.org/dwc-specimen/71267/) as Mackenzie Smith and I identified already?

Greetings @elizabeth-henson and @kyle-griffiths! I agree with Kyle that this is a rock, most likely quartz or quartzite (metamorphosed sandstone).

Greetings, @jeff-alliaume! Excellent specimens! Because myFOSSIL curators prefer having one fossil per specimen file, could you please upload each specimen into its own specimen file with photographs from several angles? From left to right, I suspect that the first and fourth are genus Cleoniceras while the third is another variety of genus…[Read more]

Greetings @brenda-phillips and @jayden-mottor! This is quite possibly a lava rock and not “fake gold” or pyrite. I can see what appears to be quartz banding, but I am having a difficult time deciphering much more than that from the picture.

Greetings, @jeff-alliaume! This is an excellent ammonite of genus Perisphinctes! Do you know the age of the rocks from which this specimen was collected? Ammonite species are notoriously difficult to ascertain, so knowing the age may help us gain a more precise identification of this specimen. For now, you can update the taxonomy to Kingdom…[Read more]

Greetings, @matthew-gramling and @pietro-ciao! I agree with Matthew that this is most likely a bryozoan rather than a graptolite. If this specimen was a graptolite, one would expect there to be a central ridge forming bilateral symmetry of the fossil, but this is noticeably absent in this specimen so a bryozoan is logical.

Greetings @elizabeth-henson! This is a marvelous petrified wood specimen! This one reminds me of the many similar specimens I have found in gravel deposits near Glendive, Montana. For more information, @mackenzie-smith would be able to provide an id!

Greetings @aj-theboss and @pietro-ciao! I am afraid this is not a coprolite but several rocks cemented together. The largest clast is an andesite lava rock that has been cemented (chemically ‘glued’) to sand and other smaller rock fragments.