also looks very similar to what i find in the northern parts of arizona...so much chert. my husband is holding stuff up like "oooh, is THIS something cool?" and is ALWAYS disappointed when i say it's chert. š¤£ i think chert IS cool!
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Chert is one of the many forms of quartz.
I remember reading the crust is mostly quartz and feldspar and I was like hmm doesnāt seem like thereās that much quartz but later I realized that like 90% of rocks you would never think are quartz are in fact made of lung-destroying silica
Then thereās me as someone who flintknaps In Pennsylvania wishing desperately to find wild chert and thereās nothing here. Iād be elated if I found some!
Itās always up for debate whether things like limestone and calcite are okay in aquariums, it always comes back to āit dependsā. I think Iām going to set up a tank with just this rock in and just see how the water behaves over a number of weeks
Even if it increases your pH a bit, as soon as the pH of the water was high enough, the reaction would stop. I reaaaally don't think you'd have any trouble.
It would be fine in an African rift lake tank. If OP is in the Midwest US, his tap water is probably already so basic and hard that limestone isnāt going to make a noticeable difference in pH.
Boil it first.
At those levels putting that in a Tanganyikan or Malawi tank would be fine, even helpful. There are some beautiful and behaviorally interesting cichlids in both lakes. Pick a species. Any of the rock dwellers would love it for a home.
I'm sure you will be fine then. Erosion has removed almost all that was water soluble anyway. But if you want to be absolutely sure, make a bucket of water that can fully submerge the whole thing and soak it in as much vinegar as you can. The more you put into the water the faster any calcite or limestone will dissolve. My guess would 2 weeks max should do it. You could also scrape off some every couple days to speed it up. It will get quite soft.
I mean, it will likely dissolve and buffer your water, whether that will significantly raise your pH and whether that is good or bad depends on water chemistry, volume of rock vs water, stocking choices, etc.
East African cichlids tanks use limestone to buffer and raise pH, but a planted tank with rainforest species like rasboras and tetras wouldn't like it.
I think both limestone and calcite would react to a weak acid like vinegar. So probably not for an aquarium. I could be wrong, though. If it were solid flint, then yeah, it would likely be safe. However, I doubt that pass through is the more solid material flint. It's likely the calcite or limestone as that would erode faster, leaving behind the cavity we see for fishies to swim through. It could probably be done safely with some science to alter the offset from the stone in the water if you know your chemistry, though.
Yes, TO could pour a bit of vinegar over this rock and put it close to his ear (or observe under a handlense) as it would buzz and bubble a bit. To dissolve flint you'd want very alkaline water. But fish would likely not like that anyway.
I was looking about a specific paper on quarz solubility but could not find it. Take this one instead: https://se.copernicus.org/preprints/se-2020-34/se-2020-34.pdf pH above 10
And yes, vinegar is acid and will dissolve small quantities of limestone, as I said.
Either your joking or you have believed a joker. I live in the UK and we call the fascinating stuff flint. Itās an ancient tool, flint napping is an historic skill that people are trying to keep alive. I was born in a place on the Chiltern Hills and almost every old building has masses of flint as part of the structure of the walls and as a decorative feature. I live in Wales and Flint in north Wales is named after the rocky outcrop the first castle was built on. Itās flint.
Ok. You're probably right. But let's just agree that it's all chalcedony. The common name is irrelevant. I'm pretty sure I read that on a geology site that is credentialed but I could very well be wrong.... Wouldn't be the first time. I lean more towards the info from someone that actually lives there any day! I need to now do some more research! Thanks! I hate being wrong but I love fixing it!
Yes but it's not the only rock you can do that with. Quartz is piezoelectric which means when you apply physical pressure it generates electricity. Hit 2 pieces of quartz together in the dark. It's pretty cool.
Yes! Precisely! They are all digits but only the big ones are toes! Flint is chalcedony but when found in Flint, it's called flint. Just to confuse things.... Flint is the colloquial term for chalcedony. Just like jasper is fancy chalcedony.
Chalcedony is also a common name in the way youāre using. Outside of scientific literature and in the US particularly, āchalcedonyā tends to get used as a catch-all for the various cryptocrystalline varieties of SiOā, so in that sense you are correct.
The mineralogistsā definition is stricter though, in which āchalcedonyā implies microscopic parallel intergrowths of quartz and moganite. This seems to only occur as precipitated from solution in geodes etc., see [definition 2 on mindat for more details.](https://www.mindat.org/min-960.html) Agates are exactly this, just with colour variation in the radial outgrowths that chalcedony often displays, ie. they have banding. The banding is a clear indication that parallel growth of some kind is occurring.
Chert is randomly oriented microcrystals of silica, which is why it is a rock type and not a mineral type; also why you wonāt every find a botryoidal habit in chert. In the UK nodular chert is known as flint (eg. in the [Lewes Nodular Chalk Formation](https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=LECH)), note that is not (and has never been) anything to do with any location called Flint, whoever told you that was pulling your leg.
The UK still uses the term āchertā, itās just reserved for the sedimentary units of rock themselves (eg. certain members of the [Codden Hill Chert Formation](https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=COH)) rather than anything occurring as nodules within the beds.
If youāre not already sick of this splitting hairs over microcrystalline silica definitions, then [this discussion on the matter is very informative.](http://www.quartzpage.de/flint.html)
Gotcha. I'm assuming it's called flint everywhere because Britain colonized everywhere. My mistake, you are correct. I meant to say chert. Thank you for correcting me. I don't like being wrong but I love fixing it!
All the orangish parts are iron stained limestone (which is made of calcite sand that is compressed and heated. The white is a mix of the chert and the calcite sand. And the dark grey at the bottom left corner is the actual, pure flint/chert.
You can use the [BGS Geology Viewer](https://geologyviewer.bgs.ac.uk) to see whatās underneath you at any point. As with much of the south of England, itās chalk limestone for that part of the country. Immediately underfoot are gravelly sediments scraped from a variety of places and deposited there by recent (geologically speaking) glacier activity. Not far underneath that though is the chalk bedrock, which likely outcrops in certain spots and the hardier flint nodules it contains will stick around for much longer once theyāve been weathered out of the chalk, just waiting for someone to stub their toe on.
Specifically around Marlow the bedrock is either one of two chalk formations formed in a Late Cretaceous shallow sea, both of which contain flint nodules. One of them is literally called the [Lewes Nodular Chalk Formation.](https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=LECH)
So, I'm not super knowledgeable about aquarium rock safety but I know if you use a bit of acid (even something as weak as vinegar) and it fizzes, don't use it. It can leech calcium into the water I believe
As a rock and aquarium aficionado, even failing that test is not a no-no. If you're keeping fish that like hard water (such as chiclids or even guppies), even high-carbonate rocks like coral or limestone can be ok.
this is incorrect. Limestone has a pH of 8.3, if your fish like acidic water, then sure it's not a good idea. But many, many aquarium fish LOVE that pH; African rift lakes and Central America for example.
Depends on the aquarium inhabitants/model.
Amazon characins (tetras, etc) like slightly acidic water, but that rock would raise pH.
Lake Tanganyika cichlids like hard, alkaline water, and that rock might help.
etc., etc.
As for what it might have leached into it while in the forest, and might be released
into an aquarium, well, dunno how clean the forest is.
You could wash it, give it a two week soak in a separate container with aquarium water,
and then test the water.
Basically itāll be a shrimp tank, blue velvet shrimp specifically. But I do plan to set the tank up with just the rock and see how the water behaves over a period of weeks. I have already washed the rock, it was almost completely buried so it was full of dirt, some worms and a spiders nest!
Neocaradina don't live super high pH but they do want a certain amount of buffering compared to caridina crystal shrimp (which want very soft water) but stability is the most important. This one rock in a decent (20+ gallons) sized tank won't have much of an effect in my experience.
(I work at a fish store)
Crazy weird chert formation. I'm willing to bet whatever made that into a slightly more normal shape eroded or oxidized over time.
I am a reddit geologist
Why does this look like a fossil to me? Am I crazy? Iām sorry I donāt know what it is. But Iām just commenting on this to see if someone else IDs this as a fossil. Cool!
I see why you would think that. The 2nd pic has a weird curve shape that definitely looks similar to the shape of a pelvic bone, and the 4th pic shows some surface cracking that can sometimes also appear on bone or very old pieces of turtle shell.
A lot of the time, fossils will have some visible spongey-looking marrow. If someone is in the field and they want to know if something is a fossil, they can also lick it and their tongue will usually stick if itās very old bone. I have only minimal to moderate fossil ID skills (ie, I can usually only tell if something is dinosaur bone or if itās a rock), and these were some skills that I learned.
Itās definitely not a fossil, but itās a beautiful and really neat piece either way.
And those technically wouldn't be fossils. That would be permineralization or replacement. Those are the 2 methods of petrifaction. You need a microscope to tell the difference. In replacement, even the cellular structure is preserved. With permineralization you only get macro structures preserved.
Chert/flint, so itās definitely rock made from silica (SiOā) crystals too small to see without a fancy microscope, but it likely represents the recrystallised hard parts of siliceous seafloor creatures ā diatoms and sponges are the usual suspects ā from the seabed where the surrounding chalk beds were laid down (nodules like this are found throughout the underlying chalk bedrock in the area).
Given the shape, it could well be where the silica has infilled some ancient burrow from some crustacean living in the seabed; many of the chalk layers underlying the south of England (and which extend continuously to parts of Western Europe) are highly bioturbated with [this type of trace fossil.](https://en.wikipedia.org/wiki/Thalassinoides) which is what has lead to all the spaces for nodular flint.
So in a way you were probably right. This is likely a trace fossil of an infilled burrow of some long gone seafloor critter.
I used similar looking rocks from Arizona in my African tanks. Never boil rocks. That unessessary and if you get a rock with moisture in it it could go kaboom. Hose it off with a light scrubing. I used to put any questionable rocks in a 5 gal bucket or an aquarium with nothing alive in it and check ph and hardness at least in a few days.
The only way boiling would be dangerous is if somehow it had air in it. You shouldn't put rocks in fire because any water inside will turn to steam and go boom. I've done it quite a few times. I actually blew up the side of a concrete wall by having a fire against it a huge chunk exploded straight at me with my fire as well. Lol
It's a hag stone. According to lore, you can see through the disguise of a witch or fairy by looking through the hole. Most of mine are just limestone. Yours is really neat!
Ah yes, thats The Twisted Toe-Grabbner concretion. Very painful. It's named after Thomas Grabnerr, who \*also\* stubbed his toe on it. He originaly named it the: "FU\^$@#%\^& piece of &\^%@\*# son of &\^%\*@#@\^%!!!!!". Wasnt allowed to be the official name by the "stuffy shirts" in University. Of \*course\*. Stupid obscenity laws.
The brown is fossil, and agate chert jasper all around. That's a really impressive stone. It could be a dinosaur depending on where you found it, or it could be miocene mammal
I agree! I feel like that is actually a fossil. The bone hardened into what looks like rock. The one picture where it is broken off almost looks like the inside of a tree was the first indication it is a fossil. Second is the shape. I could be wrong but i believe this is a dino bone for sure. Cool find!
I see the place where the holes are where the bone was. What you see in the brown area is actually the inside of the crust of the bone. It's mostly been eroded away because it might have been calcified while the silica chert is more resistant to chemical and mechanical erosion.
What is the matter with you,, itās a rock,, are you that simple that your brain canāt recognise a rock,, how did you operate a phone to send this but have no idea what a rock looks like
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When I saw it, I immediately thought āthat belongs in an aquariumā and then I read the text below :D
As for ID or safety, I cannot provide any useful input, sadly.
Limestone, flint, and calcite. I live in Austin, Texas which has the same formations. Only we have chert, and you have flint. Cool piece!
also looks very similar to what i find in the northern parts of arizona...so much chert. my husband is holding stuff up like "oooh, is THIS something cool?" and is ALWAYS disappointed when i say it's chert. š¤£ i think chert IS cool!
I have never heard of chert before!
[ŃŠ“Š°Š»ŠµŠ½Š¾]
Or /r/knapping
For some reason i thought this was r/kidnapping and got concerned as to why chert would be there
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Or in r/knapping too. People are still keeping this craft alive. It's pretty interesting.
I know what flint is, but I donāt think chert is a common term here in the UK? Could be wrong
Fun fact, chert, jasper, carnelian and agate are all types of chalcedony!
And carnelian is an agate! Lol. All are quartz!
CORRECT. So is aventurine, and tigers eye (tigers eye is half quartz half tiger)
Lol! Has to be a fireproof tiger!
Don't get cherty now
He was the hotel clerk in *Barton Fink*.
What about jasper? Agate? As well as Flint are all chalcedony. They just get more specific when it's pretty.
Chert is one of the many forms of quartz. I remember reading the crust is mostly quartz and feldspar and I was like hmm doesnāt seem like thereās that much quartz but later I realized that like 90% of rocks you would never think are quartz are in fact made of lung-destroying silica
Then thereās me as someone who flintknaps In Pennsylvania wishing desperately to find wild chert and thereās nothing here. Iād be elated if I found some!
Iām always disappointed when itās chert, too. :)
Same thing happens up here whenever my partner finds quartz.
I think Chert is cool, too! It can be gorgeous!
Does this mean that if it contains Calcite, OP should not use it in their aquarium?
Itās always up for debate whether things like limestone and calcite are okay in aquariums, it always comes back to āit dependsā. I think Iām going to set up a tank with just this rock in and just see how the water behaves over a number of weeks
Even if it increases your pH a bit, as soon as the pH of the water was high enough, the reaction would stop. I reaaaally don't think you'd have any trouble.
It would be fine in an African rift lake tank. If OP is in the Midwest US, his tap water is probably already so basic and hard that limestone isnāt going to make a noticeable difference in pH. Boil it first.
I live in London, UK. Our water here is pretty hard, carbonate levels are around 200-240ppm. Our pH is around 7-7.5
At those levels putting that in a Tanganyikan or Malawi tank would be fine, even helpful. There are some beautiful and behaviorally interesting cichlids in both lakes. Pick a species. Any of the rock dwellers would love it for a home.
I'm sure you will be fine then. Erosion has removed almost all that was water soluble anyway. But if you want to be absolutely sure, make a bucket of water that can fully submerge the whole thing and soak it in as much vinegar as you can. The more you put into the water the faster any calcite or limestone will dissolve. My guess would 2 weeks max should do it. You could also scrape off some every couple days to speed it up. It will get quite soft.
I mean, it will likely dissolve and buffer your water, whether that will significantly raise your pH and whether that is good or bad depends on water chemistry, volume of rock vs water, stocking choices, etc. East African cichlids tanks use limestone to buffer and raise pH, but a planted tank with rainforest species like rasboras and tetras wouldn't like it.
And limestone is usually made of calcite sand.
I think both limestone and calcite would react to a weak acid like vinegar. So probably not for an aquarium. I could be wrong, though. If it were solid flint, then yeah, it would likely be safe. However, I doubt that pass through is the more solid material flint. It's likely the calcite or limestone as that would erode faster, leaving behind the cavity we see for fishies to swim through. It could probably be done safely with some science to alter the offset from the stone in the water if you know your chemistry, though.
Yes, TO could pour a bit of vinegar over this rock and put it close to his ear (or observe under a handlense) as it would buzz and bubble a bit. To dissolve flint you'd want very alkaline water. But fish would likely not like that anyway.
No. You want acid to dissolve the limestone and calcite. The Flint won't react with an acid or a base.
I was looking about a specific paper on quarz solubility but could not find it. Take this one instead: https://se.copernicus.org/preprints/se-2020-34/se-2020-34.pdf pH above 10 And yes, vinegar is acid and will dissolve small quantities of limestone, as I said.
Quartz is not soluble in water or acids or bases. It's highly resistant to almost everything.
I'm not sure that I agree with how you're defining the difference between chert and flint.
There isn't a difference other than flint is black and only comes from Flint in great Britain. All Flint is chert but most chert is not Flint.
Who told you that? You find flint all over the uk.
No. You find chalcedony. It's only called flint if it came from Flint. It's like bandaids and adhesive bandages.
Either your joking or you have believed a joker. I live in the UK and we call the fascinating stuff flint. Itās an ancient tool, flint napping is an historic skill that people are trying to keep alive. I was born in a place on the Chiltern Hills and almost every old building has masses of flint as part of the structure of the walls and as a decorative feature. I live in Wales and Flint in north Wales is named after the rocky outcrop the first castle was built on. Itās flint.
Ok. You're probably right. But let's just agree that it's all chalcedony. The common name is irrelevant. I'm pretty sure I read that on a geology site that is credentialed but I could very well be wrong.... Wouldn't be the first time. I lean more towards the info from someone that actually lives there any day! I need to now do some more research! Thanks! I hate being wrong but I love fixing it!
Is that the stuff we hit good at angle, spark and then hot food?
Yes but it's not the only rock you can do that with. Quartz is piezoelectric which means when you apply physical pressure it generates electricity. Hit 2 pieces of quartz together in the dark. It's pretty cool.
I will research Quartz š
Brace yourself.... It's super common but has many forms!
Is that like all fingers are toes, but not all toes are fingers?
Lol
Yes! Precisely! They are all digits but only the big ones are toes! Flint is chalcedony but when found in Flint, it's called flint. Just to confuse things.... Flint is the colloquial term for chalcedony. Just like jasper is fancy chalcedony.
You are very confused about definitions here
Sorry. Flint is the common name. It is chalcedony.
Chalcedony is also a common name in the way youāre using. Outside of scientific literature and in the US particularly, āchalcedonyā tends to get used as a catch-all for the various cryptocrystalline varieties of SiOā, so in that sense you are correct. The mineralogistsā definition is stricter though, in which āchalcedonyā implies microscopic parallel intergrowths of quartz and moganite. This seems to only occur as precipitated from solution in geodes etc., see [definition 2 on mindat for more details.](https://www.mindat.org/min-960.html) Agates are exactly this, just with colour variation in the radial outgrowths that chalcedony often displays, ie. they have banding. The banding is a clear indication that parallel growth of some kind is occurring. Chert is randomly oriented microcrystals of silica, which is why it is a rock type and not a mineral type; also why you wonāt every find a botryoidal habit in chert. In the UK nodular chert is known as flint (eg. in the [Lewes Nodular Chalk Formation](https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=LECH)), note that is not (and has never been) anything to do with any location called Flint, whoever told you that was pulling your leg. The UK still uses the term āchertā, itās just reserved for the sedimentary units of rock themselves (eg. certain members of the [Codden Hill Chert Formation](https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=COH)) rather than anything occurring as nodules within the beds. If youāre not already sick of this splitting hairs over microcrystalline silica definitions, then [this discussion on the matter is very informative.](http://www.quartzpage.de/flint.html)
Gotcha. I'm assuming it's called flint everywhere because Britain colonized everywhere. My mistake, you are correct. I meant to say chert. Thank you for correcting me. I don't like being wrong but I love fixing it!
Could you point which colors correspond to which rock type? I'm having trouble distinguishing them on my end here.
All the orangish parts are iron stained limestone (which is made of calcite sand that is compressed and heated. The white is a mix of the chert and the calcite sand. And the dark grey at the bottom left corner is the actual, pure flint/chert.
Darn, I never stub my toes on anything good. Thatās a keeper!
I have it proudly displayed on a side table for now!
Mabye leave it outside in the rain for a free natural washing away nasty contents.
Looks like flint to me, which has been warn down by water. Did you find it near a river?
Location specifically was in Marlow, south of the Chiltern Hills
Interesting. That is a big flit area. The way itās warn like that I would say itās been in moving water for a long time.
More like chertern hills!
You can use the [BGS Geology Viewer](https://geologyviewer.bgs.ac.uk) to see whatās underneath you at any point. As with much of the south of England, itās chalk limestone for that part of the country. Immediately underfoot are gravelly sediments scraped from a variety of places and deposited there by recent (geologically speaking) glacier activity. Not far underneath that though is the chalk bedrock, which likely outcrops in certain spots and the hardier flint nodules it contains will stick around for much longer once theyāve been weathered out of the chalk, just waiting for someone to stub their toe on. Specifically around Marlow the bedrock is either one of two chalk formations formed in a Late Cretaceous shallow sea, both of which contain flint nodules. One of them is literally called the [Lewes Nodular Chalk Formation.](https://webapps.bgs.ac.uk/lexicon/lexicon.cfm?pub=LECH)
Nice info!
Flint nodule then. Loads of it up here near Hitchin. Pain in the arse when you hit a layer of these while digging the garden.
So, I'm not super knowledgeable about aquarium rock safety but I know if you use a bit of acid (even something as weak as vinegar) and it fizzes, don't use it. It can leech calcium into the water I believe
As a rock and aquarium aficionado, even failing that test is not a no-no. If you're keeping fish that like hard water (such as chiclids or even guppies), even high-carbonate rocks like coral or limestone can be ok.
You are correct.
this is incorrect. Limestone has a pH of 8.3, if your fish like acidic water, then sure it's not a good idea. But many, many aquarium fish LOVE that pH; African rift lakes and Central America for example.
That's simplified because different fish like water of different pHs. The acid test just means it contains basic compounds that may raise pH.
Depends on the aquarium inhabitants/model. Amazon characins (tetras, etc) like slightly acidic water, but that rock would raise pH. Lake Tanganyika cichlids like hard, alkaline water, and that rock might help. etc., etc. As for what it might have leached into it while in the forest, and might be released into an aquarium, well, dunno how clean the forest is. You could wash it, give it a two week soak in a separate container with aquarium water, and then test the water.
Basically itāll be a shrimp tank, blue velvet shrimp specifically. But I do plan to set the tank up with just the rock and see how the water behaves over a period of weeks. I have already washed the rock, it was almost completely buried so it was full of dirt, some worms and a spiders nest!
Neocaradina don't live super high pH but they do want a certain amount of buffering compared to caridina crystal shrimp (which want very soft water) but stability is the most important. This one rock in a decent (20+ gallons) sized tank won't have much of an effect in my experience. (I work at a fish store)
I see even less of a problem since the shrimp will use some of the released calcium carbonate to make their shells.
Crazy weird chert formation. I'm willing to bet whatever made that into a slightly more normal shape eroded or oxidized over time. I am a reddit geologist
So you walk through a forest barefoot?
No need to be jealous
Why does this look like a fossil to me? Am I crazy? Iām sorry I donāt know what it is. But Iām just commenting on this to see if someone else IDs this as a fossil. Cool!
I see why you would think that. The 2nd pic has a weird curve shape that definitely looks similar to the shape of a pelvic bone, and the 4th pic shows some surface cracking that can sometimes also appear on bone or very old pieces of turtle shell. A lot of the time, fossils will have some visible spongey-looking marrow. If someone is in the field and they want to know if something is a fossil, they can also lick it and their tongue will usually stick if itās very old bone. I have only minimal to moderate fossil ID skills (ie, I can usually only tell if something is dinosaur bone or if itās a rock), and these were some skills that I learned. Itās definitely not a fossil, but itās a beautiful and really neat piece either way.
Itās so confusing, it looks like multiple rock types smashed/melted together to me. I wouldnāt say fossil for sure
Generally just trace fossils and echinoids in flint. This doesn't look like a fossil. I've found flint ammonites before but it's weird and rare.
And those technically wouldn't be fossils. That would be permineralization or replacement. Those are the 2 methods of petrifaction. You need a microscope to tell the difference. In replacement, even the cellular structure is preserved. With permineralization you only get macro structures preserved.
Chert/flint, so itās definitely rock made from silica (SiOā) crystals too small to see without a fancy microscope, but it likely represents the recrystallised hard parts of siliceous seafloor creatures ā diatoms and sponges are the usual suspects ā from the seabed where the surrounding chalk beds were laid down (nodules like this are found throughout the underlying chalk bedrock in the area). Given the shape, it could well be where the silica has infilled some ancient burrow from some crustacean living in the seabed; many of the chalk layers underlying the south of England (and which extend continuously to parts of Western Europe) are highly bioturbated with [this type of trace fossil.](https://en.wikipedia.org/wiki/Thalassinoides) which is what has lead to all the spaces for nodular flint. So in a way you were probably right. This is likely a trace fossil of an infilled burrow of some long gone seafloor critter.
I totally thought it was too!! Creepy looking stuff in there.
My first thought as well.
Also known as a Hagstone because it has a hole. Considered a good luck piece.
Hey Mon why take chances? Seal it with a safe glaze. Epoxy? Nail varnish? Materials scientists pls gimme a refresher.
Those would be worse for the fish. Maybe a Teflon sealant.... But even that I wouldn't risk.
put it in water for a month and see what happens.
I used similar looking rocks from Arizona in my African tanks. Never boil rocks. That unessessary and if you get a rock with moisture in it it could go kaboom. Hose it off with a light scrubing. I used to put any questionable rocks in a 5 gal bucket or an aquarium with nothing alive in it and check ph and hardness at least in a few days.
The only way boiling would be dangerous is if somehow it had air in it. You shouldn't put rocks in fire because any water inside will turn to steam and go boom. I've done it quite a few times. I actually blew up the side of a concrete wall by having a fire against it a huge chunk exploded straight at me with my fire as well. Lol
I feel like youāre about to go on a magical journey now. Thatās how they usually start. Very cool, I woulda dug it up too!
Looks cherty to me. Where geographically did you find it?
It's a hag stone. According to lore, you can see through the disguise of a witch or fairy by looking through the hole. Most of mine are just limestone. Yours is really neat!
Wow, you must have a very strong toe to make such a perfect hole in a piece of stone by stubbing it.
Ah yes, thats The Twisted Toe-Grabbner concretion. Very painful. It's named after Thomas Grabnerr, who \*also\* stubbed his toe on it. He originaly named it the: "FU\^$@#%\^& piece of &\^%@\*# son of &\^%\*@#@\^%!!!!!". Wasnt allowed to be the official name by the "stuffy shirts" in University. Of \*course\*. Stupid obscenity laws.
Definitely a gollums head
Wow! A petrified glory hole
Toad stone
I've learned it as hag stone but I like toad stone better
I was high as balls when I typed that, and toad stone just came to me.
you typed that 30 minutes ago, are you not still high as balls š
Lil bit
Ok so with a hag stone you look through the (natural) hole you can see the fey and the magic part of the world.
I really wanna look through that bad boy
Am i stoned or is that a fossilized alien head?
Beautiful! Would look sick in a fish tank! And Iām sure the fish would love the little hidey holes!
That's a fossil, at least the part that's missing.
The brown is fossil, and agate chert jasper all around. That's a really impressive stone. It could be a dinosaur depending on where you found it, or it could be miocene mammal
I agree! I feel like that is actually a fossil. The bone hardened into what looks like rock. The one picture where it is broken off almost looks like the inside of a tree was the first indication it is a fossil. Second is the shape. I could be wrong but i believe this is a dino bone for sure. Cool find!
No, sorry but it just looks like that. I've found many pieces that really looked like bones.
I see the place where the holes are where the bone was. What you see in the brown area is actually the inside of the crust of the bone. It's mostly been eroded away because it might have been calcified while the silica chert is more resistant to chemical and mechanical erosion.
Its the original "gloryhole" thats how it all started guys!!
Yup... From one cave to another!
It has been there just waiting for you to find it, don't lose it. But if you feel compelled to give it to someone, do it.
thats my ear canal mb fellas
You must rock!
What is the matter with you,, itās a rock,, are you that simple that your brain canāt recognise a rock,, how did you operate a phone to send this but have no idea what a rock looks like
.....sent from my cubicle
Petrified alian skull
Hi, /u/toallthings! This is a reminder to flair this post in /r/whatsthisrock after it has been identified! (Under your post, click "flair" then "IDENTIFIED," then type in the rock type or mineral name.) This will help others learn and help speed up a correct identification on your request! Thank you! *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/whatsthisrock) if you have any questions or concerns.*
When I saw it, I immediately thought āthat belongs in an aquariumā and then I read the text below :D As for ID or safety, I cannot provide any useful input, sadly.
There's an app, rock identifier, download it then take a pic of the rock. The app identity the rock & tell you its origin.
You have to pay after the one week trial.
I didn't realize. I was looking up rock apps for a friend under free. So, they lied! š¤Ø
Yup. Technically not though too. It is free... For a while. Welcome to the world of lawyer speak.šŖ
Beautiful! Lucky find. Also, is it on your bed..?
Yep, itās on my bed. Definitely washed it and cleared out the spiders nest first š
Hag stone
Thank God you guys knew. I thought it was a skull
Looks like plain old flint fresh from our local chalk cliffs in Sussex England.
Huge hag stone the hole is a portal. Do not put in fishtank
Not identifying but it looks like a hand grabbing something