2
$\begingroup$

Found in a wooded area after being dug up by my dog.
Could not find anything similar online so I thought it best to ask those with far more experience.
I'm guessing that it could be petrified wood?
I have next to no geological experience so I look forward to your opinions. enter image description here

enter image description here

$\endgroup$

closed as off-topic by Leukocyte, trond hansen, Fred, BillDOe, arkaia Sep 1 at 23:05

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions about rock identification requests are off-topic. For more information, see the announcement on meta." – Leukocyte, trond hansen, Fred, BillDOe, arkaia
If this question can be reworded to fit the rules in the help center, please edit the question.

  • 1
    $\begingroup$ It's chert, stained red by iron oxides (aka rust). Probably not petrified wood. $\endgroup$ – Gimelist Sep 12 '17 at 0:00
  • $\begingroup$ @Michael I will accept that as an answer. $\endgroup$ – Raphael_Python Sep 12 '17 at 9:39
  • $\begingroup$ @Michael I spent some time looking at Chert and I can see you must be correct. I based my assumption of petrified wood off an image I found online. I can clearly see now that my chert doesn't show any of the identifying features found in petrified wood. $\endgroup$ – Raphael_Python Sep 12 '17 at 9:42
5
$\begingroup$

It is chert infused with iron oxide.

$\endgroup$
  • $\begingroup$ please give more information in this answer by telling some details about what chert is and how it is made its hardness and maby put in a link to more information. $\endgroup$ – trond hansen Sep 13 '17 at 7:01
  • $\begingroup$ @trondhansen I have answered the question. Writing encyclopedia articles is not part of the assignment. The Wikipedia already has articles on chert, or he could just buy a book on chert like Sieveking's 2011 study. $\endgroup$ – Tyler Durden Sep 13 '17 at 13:11
  • $\begingroup$ @trondhansen myself and others already did that. I don't see any need in doing that for each and every question about chert that we have here. $\endgroup$ – Gimelist Sep 15 '17 at 6:59
  • $\begingroup$ ok i am sorry i was not aware it was a duplicate. $\endgroup$ – trond hansen Sep 15 '17 at 7:39
  • $\begingroup$ I answered one about chert today too. it's compressed limestone from sea sediment which has undergone a kind of compression metamorphosis, that one is not pure silicon, which is more glassy, it still contains a bit of CaCO3, so it is more dull than pure silicon. the iron indeed gives it that color, i found a jade colored chert recently myself. the silicon and chalk inside the sediment have a weird gel liquification disassociation which forms flint and chalk in bands and nodules. chert is half way between limestone and flint. $\endgroup$ – com.prehensible Sep 21 '17 at 9:06
-1
$\begingroup$

I found the same as that with veins of pure SiO2 in it, which i call the spunkules rock: enter image description here Unfortunately, i didn't have space in my bag to take the spunkules rock with me.

This rock is special because the temperature has been high enough for a flint formation has started to happen, and if the temperature had risen and the minerals had been more caramelized, they would have made larger blobs, and made serious lumps. For some reason, perhaps the presence of iron, the SiO2 ionic repulsion from the surrounding stone and it's coagulation into cracks has a different dendrite appearance compare do the bands of marbled flint and chert. enter image description here

your one probably started off as one of these and then got compressed to chert: http://hassansand.com/wp-content/uploads/3_4_3RedLimestoneNew.jpg

$\endgroup$
  • $\begingroup$ There are quite a lot of wrong statements in your answer. Rocks do not get caramelised.This texture is not dendritic. Flint/chert can form at extremely low temperatures (think seafloor). There is no such thing as "SiO2 ionic repulsion". What is "marbled"? Marble in geology means metamorphosed carbonates. $\endgroup$ – Gimelist Sep 22 '17 at 10:36
  • $\begingroup$ Fair enough, marbling in wiktionary means mottled and banded. Regarding ionic attraction, did you ever charge the plastic of a ruler to give it a static charge and check what it does to water? ions have charge, so by what mechanism do you suggest that crystals form in malleable caramelized rocks that are under high pressure? they are good enough to be called dendritic, they branch off from a main stem, technically there is probably a better name, it's more dendritic than it is globular :) google.fr/search?q=dendritic+rock+surface&num=100 $\endgroup$ – com.prehensible Sep 22 '17 at 18:53
  • $\begingroup$ Marbling is a term used in the meat industry ("marbled steak"), not in geology. Ions do indeed have charge, and that charge is responsible for many geological and geochemical processes. However, "SiO2 ionic repulsion" is not what's happening here. This is the dissolution of silica in hydrothermal fluids at high pressure, and reprecipitation during decompression into a network of veins (that are not dendritic). And again, I do not know what you mean by "caramelised" and what does that have to do with geology. $\endgroup$ – Gimelist Sep 23 '17 at 5:39
  • $\begingroup$ Thanks, that's a fair comment, especially if you think they're quartz veins. That implies that the very tough chert was fragmented into very small pieces of gravel, and that there was space for air/water to get inside it after it was shocked. To fracture the stone in that fasion, it implies an exotic seismic shock wave which can fracture a zone of chert into small pieces. The cracks are similar to semi-soft clay being cracked, it suggests plasticity and brittlenes of the chert, because if you crack play dough it can result in that fracture shape, i thought the chert was too brittle. $\endgroup$ – com.prehensible Sep 23 '17 at 10:31
  • $\begingroup$ The fractures are often incomplete complete, i.e. they run a few millimeters and then the fractures stop, which means that there was considerable plasticity in the chert. and when something is plastic or malleable, it cannot crack in a brittle way, and it also implies a seismic event, as if the rock was cracked with a sledgehammer, and yet the fractures don't look like a brittle substance because it's often play dough / plastic / short fractures. it's weird. but their's air bubbles in it so obviously you are right. $\endgroup$ – com.prehensible Sep 23 '17 at 10:39

Not the answer you're looking for? Browse other questions tagged or ask your own question.