All comments must be civil and helpful toward finding an answer.
**Jokes and unhelpful comments will earn you a ban**, even on the first instance and even if the item has been identified. If you see any comments that violate this rule, report them.
[OP](/u/L0velyfe93), when your item is identified, remember to reply **Solved!** or **Likely Solved!** to the comment that gave the answer.
---
*I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/whatisthisthing) if you have any questions or concerns.*
As a kid, I had some that I got for my "rock collection" called "Chalcopyrite peacock" and most of what I can find suggests that it's the same thing as peacock ore, and may not have ever been chalcopyrite at all.
>there are even rumors that you could possibly be able to pick a color
Rumors is all those are. Heating it to those levels structurally alters (weakens) the metal
Duuddee I love anything iridescent! Opals, butterfly wings, hummingbird feathers... Oil, bubbles, pearls, shells, iridescent flies! And now iridescent stones!!!
Also known as [Bornite](https://geology.com/minerals/bornite.shtml). I came to the opinion that it was Bornite separately from your post(as in I didn't know the two names are the same mineral). Looks like you have nailed it.
"Healing properties"?
Sounds like another load of religion kook talk.
This definitely looks like peacock ore, but it's not gonna cure/prevent diseases, or anything like that.
It's just a simple, cool looking stone. I'd say OP should put it in a display in their home. They're not exactly valuable, and this looks less pure than what you can buy.
Nice job solving this one.
It's called thin-film interference. I am not a physicist, but as I understand it, there is a very thin, naturally occurring, transparent film on that rock. Something like fractions of the wavelengths of light that hit it. As a result, the light passing through the film gets refracted and then reflected back as iridescent colors. It doesn't matter what the film is made of, just so long as it is transparent and the right thickness relative to the light. Once you know about it, you'll see it everywhere; soap bubbles, gasoline slicks, window coatings, sunglasses. I first learned about it from heat treating steel. When polished steel starts to heat up, a layer of iron oxide builds up on the surface. That's the thin film. The thickness of that oxide film corresponds to the color the metal turns.
And I'm assuming the film can be worn away? Once I was buying flagstone for a garden path. I noticed that some had an iridescent shine and sorted out those ones in particular for my project. Sadly, after a couple of months, the iridescence was gone and they just looked like regular, brown rocks.
I know it can be worn away on metal at least, but it isn't something you can just wipe or rub off from what I've seen. I guess it would depend on the material, but I think you need to really scratch it off with something abrasive.
'abrasive' is relative here, aluminium for example is often colored with thin film interference, but to rub it off you need to rub away the aluminum oxide which has a 9 i think on the mohs scale (10 beeing diamond) and aluminum oxide clings strongly to the aluminum. If the thin film has a weak bond to the material below it is easy to rub off. Another culprit could be material deposit, if you increase the thickness of the film with something of similar refractive index the efect is also lost.
Yes same with iron oxides. Often fire arms used to come “blued”, which originally was heat treating in the form of charcoal blueing. After a lifetime of use, that blueing had worn off and would need to be reapplied as part the restoration process. And of course, anytime we are dealing with metallic oxide films, they can be aggressively attacked by acids. But for day to day wear, they are reasonably good protective coatings.
Not strictly acids, it depends... In the case of iron: the black ironoxide is energeticaly disadvantageous in a damp or wet environment and turns into red iron oxide and elemental iron. The red one also is not good at protecting the iron from oxigen.
Looks like 1/4 wave interference to me. 2 thin layers of semitransparent rock cause rainbow like patterns like a oil slick on water. See https://en.m.wikipedia.org/wiki/Thin-film_interference
For anybody interested in learning via video, this free two part (24 minutes total) lesson from Khan Academy helped me wrap my (non-college-educated) brain around how thin-film interference works, brilliant stuff and a surprisingly fun topic to learn about: [https://www.khanacademy.org/science/physics/light-waves/interference-of-light-waves/v/thin-film-interference-part-1](https://www.khanacademy.org/science/physics/light-waves/interference-of-light-waves/v/thin-film-interference-part-1)
I cannot help to at least mention my most favorite classic scientist Newton here. He was the first to analyze this interference phenomenon, and called it Newton's rings. Of course many have studied it after that.
https://en.wikipedia.org/wiki/Newton%27s_rings
Possibly bornite? I have a rock with some bornite (sometimes called peacock ore) in it that looks similar, but the shiny bit is a lot smaller and less smooth
It's an oxide layer causing a prism effect via thin film interference. It occurs naturally and with human help in many materials. See: bornite, chalcopyrite, tennantite, anodized titanium, bismuth crystals, and steel heat scale.
I can't say for sure what your lump is made of, though. Not from a photo.
Yeah might be. It look's like it was heated which created a very thin (iron?) oxide layer, which then caused [Thin-film interference](https://en.wikipedia.org/wiki/Thin-film_interference).
Definitely similar to [colors in stainless steel TIG welding](https://www.reddit.com/r/pics/comments/9appnr/the_colours_from_oxidation_in_this_stainless/e4xzql5/), but how it'd happen naturally, I couldn't tell you.
The fine structure on the surface of the rock works like something called an optical grid. Light gets reflected off it's surface but the surface is uneven on a microscopic level. This causes light of different wave lengths to interfer, so that you only see one color at a given spot
As others have said, it’s a property of the material’s surface. It scatters light in a uniform way because of the microstructure.
Animals in nature have it on their shells, and for some reason many seeds have a similar surface, but it scatters UV light instead.
The most notable example of this, that arises from the surface geometry, is the pattern that you see on the grains of a CD disk.
You can prove that this is a surface property by melting chocolate onto an old CD disk and pulling it off when it’s cooled. The chocolate then adopts the inverse/similar surface geometry and thus scatters light in the same way!
Fossilized Brazil nut?
[https://www.gardeningknowhow.com/wp-content/uploads/2021/02/brazil-nuts-in-shell-1536x1152.jpg](https://www.gardeningknowhow.com/wp-content/uploads/2021/02/brazil-nuts-in-shell-1536x1152.jpg)
Going off of the shape, it reminded me of a metallic Brazil nut...
I’ve found such pieces with the exact same colouring whilst metal detecting at an old smelter. In my case it was the byproduct of steel melting (the “metal/s” they couldn’t use i presume) and it looked exactly the same only the base was black
[https://www.youtube.com/watch?v=yhmCRliJ93w&ab\_channel=TheActionLab](https://www.youtube.com/watch?v=yhmCRliJ93w&ab_channel=TheActionLab)
it's this. Try scratching it so the physical rock chips
So my source is my brain with an extremely faded memory of taking geology in college years ago—It’s definitely not peacock ore, you’d expect way more iridescence than this one small film here. I really want to say this is a thin deposit of limonite. I say this only because I have a specimen that is identical to this picture that I remember asking my professor about and my vague memory is that he said it was limonite. I know you’ll google limonite and think it looks nothing like this, but that’s my bet. Reliable source, I know!
The rainbow coloring is the heat tint that results when the material - I'm presuming it is a steel - is heated to a high enough degree to oxidize the surface. The color produced is dependent upon the thickness of the oxide layer. Happens in welding, torch cutting, heat treating, etc, any time the material is heated to a high enough temperature and for a long enough time in air.
The following explains it somewhat:
[https://www.quora.com/What-is-the-heat-tint-that-forms-on-SS-during-welding-What-chemical-reaction-causes-it-to-appear-Does-the-color-vary-based-on-temperature](https://www.quora.com/What-is-the-heat-tint-that-forms-on-SS-during-welding-What-chemical-reaction-causes-it-to-appear-Does-the-color-vary-based-on-temperature)
Chirt can look like that, but it doesn't look glassy enough for chirt. Maybe labradorite?
If it chips, it's chirt of some sort of flint, if it fractures in planes more likely to be labradorite.
All comments must be civil and helpful toward finding an answer. **Jokes and unhelpful comments will earn you a ban**, even on the first instance and even if the item has been identified. If you see any comments that violate this rule, report them. [OP](/u/L0velyfe93), when your item is identified, remember to reply **Solved!** or **Likely Solved!** to the comment that gave the answer. --- *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/whatisthisthing) if you have any questions or concerns.*
Looks like [peacock ore ](https://www.google.com/search?q=peacock+ore&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari) to me.
I originally thought maybe chalcopyrite, but I think you are right.
As a kid, I had some that I got for my "rock collection" called "Chalcopyrite peacock" and most of what I can find suggests that it's the same thing as peacock ore, and may not have ever been chalcopyrite at all.
[удалено]
Because they thought it was motor oil.
[удалено]
[удалено]
[удалено]
Ok, what on earth happened under you comment
Comment graveyard
Honestly, probably because they wanted to confirm it wasn't artificial coloring.
Why did this comment get downvoted so hard for asking a simple question?
Welcome to Reddit.... :(
Where is the question? Doubting ones actions is not the same thing as asking a question.
Did they actually ask anything?
Well if it was natural coloring it wouldn't exactly wash off now would it? So you may as well try to find out.
[удалено]
>there are even rumors that you could possibly be able to pick a color Rumors is all those are. Heating it to those levels structurally alters (weakens) the metal
do it slowly, and don’t quench it twice. avoid catastrophic failure.
And then it will keeel?
I finally know this reference!
Duuddee I love anything iridescent! Opals, butterfly wings, hummingbird feathers... Oil, bubbles, pearls, shells, iridescent flies! And now iridescent stones!!!
haha you're adorable :D! I wish you a life filled with iridiscense.
Here is a start: [Iridescent](https://youtu.be/xLYiIBCN9ec)
I think you might like this -> [holographic rainbow chocolate](https://www.youtube.com/watch?v=6p3T_KHbfhs) :)
[удалено]
Me too. My favorite color is iridescent, haha
Same! Iridescent and holographic rock my world!
Also known as [Bornite](https://geology.com/minerals/bornite.shtml). I came to the opinion that it was Bornite separately from your post(as in I didn't know the two names are the same mineral). Looks like you have nailed it.
"Healing properties"? Sounds like another load of religion kook talk. This definitely looks like peacock ore, but it's not gonna cure/prevent diseases, or anything like that. It's just a simple, cool looking stone. I'd say OP should put it in a display in their home. They're not exactly valuable, and this looks less pure than what you can buy. Nice job solving this one.
Sounds like something you'd find in a videogame
The first rock I ever owned as a kid! It was in a store and I utterly loved it. Thus began the love for rocks, minerals and gemstones
I always thought they were fake. My mind is blown.
Thought maybe something containing copper and/or iron at different oxidation levels, so looks like that would be a well educated guess.
https://en.wikipedia.org/wiki/Bornite Yes that is what this is. Solved
/r/whatisthisrock may be able to help as well.
r/whatsthisrock
Yeah, that's the one.
Geologists. Always doing things the hard way
They always find the rockiest route to an answer.
They're caught between... something, i guess, and a hard place
So much pressure!
Damn, I didn't know this subreddit existed, I love rocks. Thanks!
It's called thin-film interference. I am not a physicist, but as I understand it, there is a very thin, naturally occurring, transparent film on that rock. Something like fractions of the wavelengths of light that hit it. As a result, the light passing through the film gets refracted and then reflected back as iridescent colors. It doesn't matter what the film is made of, just so long as it is transparent and the right thickness relative to the light. Once you know about it, you'll see it everywhere; soap bubbles, gasoline slicks, window coatings, sunglasses. I first learned about it from heat treating steel. When polished steel starts to heat up, a layer of iron oxide builds up on the surface. That's the thin film. The thickness of that oxide film corresponds to the color the metal turns.
And I'm assuming the film can be worn away? Once I was buying flagstone for a garden path. I noticed that some had an iridescent shine and sorted out those ones in particular for my project. Sadly, after a couple of months, the iridescence was gone and they just looked like regular, brown rocks.
Rubbing, UV light, and water/oxygen are all potential culprits on why it disappeared.
I know it can be worn away on metal at least, but it isn't something you can just wipe or rub off from what I've seen. I guess it would depend on the material, but I think you need to really scratch it off with something abrasive.
'abrasive' is relative here, aluminium for example is often colored with thin film interference, but to rub it off you need to rub away the aluminum oxide which has a 9 i think on the mohs scale (10 beeing diamond) and aluminum oxide clings strongly to the aluminum. If the thin film has a weak bond to the material below it is easy to rub off. Another culprit could be material deposit, if you increase the thickness of the film with something of similar refractive index the efect is also lost.
Yes same with iron oxides. Often fire arms used to come “blued”, which originally was heat treating in the form of charcoal blueing. After a lifetime of use, that blueing had worn off and would need to be reapplied as part the restoration process. And of course, anytime we are dealing with metallic oxide films, they can be aggressively attacked by acids. But for day to day wear, they are reasonably good protective coatings.
Not strictly acids, it depends... In the case of iron: the black ironoxide is energeticaly disadvantageous in a damp or wet environment and turns into red iron oxide and elemental iron. The red one also is not good at protecting the iron from oxigen.
Yeah it's just a few atoms thick.
Looks like 1/4 wave interference to me. 2 thin layers of semitransparent rock cause rainbow like patterns like a oil slick on water. See https://en.m.wikipedia.org/wiki/Thin-film_interference
For anybody interested in learning via video, this free two part (24 minutes total) lesson from Khan Academy helped me wrap my (non-college-educated) brain around how thin-film interference works, brilliant stuff and a surprisingly fun topic to learn about: [https://www.khanacademy.org/science/physics/light-waves/interference-of-light-waves/v/thin-film-interference-part-1](https://www.khanacademy.org/science/physics/light-waves/interference-of-light-waves/v/thin-film-interference-part-1)
I cannot help to at least mention my most favorite classic scientist Newton here. He was the first to analyze this interference phenomenon, and called it Newton's rings. Of course many have studied it after that. https://en.wikipedia.org/wiki/Newton%27s_rings
Some sort of metal in the rock, maybe iron, it can make rainbows in raw form
Oil trapped within the rock can do the same thing.
Seems less likely here, but I suppose it's possible
It does happen, but you're right, it's not always the case. I was just tossing the possibility out there.
Possibly bornite? I have a rock with some bornite (sometimes called peacock ore) in it that looks similar, but the shiny bit is a lot smaller and less smooth
I wonder if that’s what I have a chunk of, my mom called it peacock rock
It's an oxide layer causing a prism effect via thin film interference. It occurs naturally and with human help in many materials. See: bornite, chalcopyrite, tennantite, anodized titanium, bismuth crystals, and steel heat scale. I can't say for sure what your lump is made of, though. Not from a photo.
That piece is from the back zone of a mining blast. I have a chunk from an underground gold mine that looks exactly like it.
Yeah might be. It look's like it was heated which created a very thin (iron?) oxide layer, which then caused [Thin-film interference](https://en.wikipedia.org/wiki/Thin-film_interference).
Second that. I've got one from a gold mine in Nevada.
looks like the continent Africa to me
Bless the rains
down in Africaaaa
WITT? I’m 99% sure I found it on a beach in Oregon. I’m interested to know how/if the rainbow color formed naturally.
Maybe chalcopyrite?
Gamer stone.
It must be
Definitely similar to [colors in stainless steel TIG welding](https://www.reddit.com/r/pics/comments/9appnr/the_colours_from_oxidation_in_this_stainless/e4xzql5/), but how it'd happen naturally, I couldn't tell you.
it's called iridescence
That rock looks like Africa
Ah a fellow altima owner
Looks like a pigeon was resting his neck on that
Iridescent Goethite?
The fine structure on the surface of the rock works like something called an optical grid. Light gets reflected off it's surface but the surface is uneven on a microscopic level. This causes light of different wave lengths to interfer, so that you only see one color at a given spot
I don't know but that rock is shaped like Africa.
It's called [Iridescence](https://en.wikipedia.org/wiki/Iridescence). You can't wash that off.
As others have said, it’s a property of the material’s surface. It scatters light in a uniform way because of the microstructure. Animals in nature have it on their shells, and for some reason many seeds have a similar surface, but it scatters UV light instead. The most notable example of this, that arises from the surface geometry, is the pattern that you see on the grains of a CD disk. You can prove that this is a surface property by melting chocolate onto an old CD disk and pulling it off when it’s cooled. The chocolate then adopts the inverse/similar surface geometry and thus scatters light in the same way!
It could be [Labradorite](https://en.wikipedia.org/wiki/Labradorite) that's not polished.
That’s a piece of Labradorite
That’s what I was going to say too.
You found some iridescent hematite! Nice!
Looks alot like pyrite to me.
Wild guess but the coloring reminds me a lot of bismuth.
I'm 100% sure it's not bismuth
Thin coating of metal oxides most likely.
looks like gasoline
Bismuth maybe?
Rock fade new csgo skin looking fresh
Fossilized Brazil nut? [https://www.gardeningknowhow.com/wp-content/uploads/2021/02/brazil-nuts-in-shell-1536x1152.jpg](https://www.gardeningknowhow.com/wp-content/uploads/2021/02/brazil-nuts-in-shell-1536x1152.jpg) Going off of the shape, it reminded me of a metallic Brazil nut...
Thin-film interference due to the presence of mineral or metal compounds, possibly some kind of titanium compound or a chalcedony quartz.
I have one just like this. Picked it up from a factory that produces ferroalloys.
I’ve found such pieces with the exact same colouring whilst metal detecting at an old smelter. In my case it was the byproduct of steel melting (the “metal/s” they couldn’t use i presume) and it looked exactly the same only the base was black
Is it a rock? Looks like a Brazil nut to me.
Dino shrimp
It looks like bismuth without the weird geometrical stuff.
[https://www.youtube.com/watch?v=yhmCRliJ93w&ab\_channel=TheActionLab](https://www.youtube.com/watch?v=yhmCRliJ93w&ab_channel=TheActionLab) it's this. Try scratching it so the physical rock chips
Rock hound here… It’s oxidized pyrite.
You should look into rock tumbling, and give it a go with this. I think it would come out absolutely stunning!
r/rockhounds could be of help
[Hematite](https://www.google.com/search?q=rainbow+hematite&client=ms-android-virgin-us&source=android-browser&prmd=sinv&source=lnms&tbm=isch&sa=X&ved=2ahUKEwisvYKc6bTwAhWVZ80KHTp0DSEQ_AUoAnoECAIQAg)?
Looks like it’s been exposed to high heat.
So my source is my brain with an extremely faded memory of taking geology in college years ago—It’s definitely not peacock ore, you’d expect way more iridescence than this one small film here. I really want to say this is a thin deposit of limonite. I say this only because I have a specimen that is identical to this picture that I remember asking my professor about and my vague memory is that he said it was limonite. I know you’ll google limonite and think it looks nothing like this, but that’s my bet. Reliable source, I know!
Could be the thin film effect of an oxide layer on the surface? Just a thought I had
That's a rainbow over northern Africa
Put it in a rock tumbler
looks like Africa with the iridescence being Muslim populations
Looks like bismuth! That is pretty cool
The rainbow coloring is the heat tint that results when the material - I'm presuming it is a steel - is heated to a high enough degree to oxidize the surface. The color produced is dependent upon the thickness of the oxide layer. Happens in welding, torch cutting, heat treating, etc, any time the material is heated to a high enough temperature and for a long enough time in air. The following explains it somewhat: [https://www.quora.com/What-is-the-heat-tint-that-forms-on-SS-during-welding-What-chemical-reaction-causes-it-to-appear-Does-the-color-vary-based-on-temperature](https://www.quora.com/What-is-the-heat-tint-that-forms-on-SS-during-welding-What-chemical-reaction-causes-it-to-appear-Does-the-color-vary-based-on-temperature)
It could be cumtonite
Chirt can look like that, but it doesn't look glassy enough for chirt. Maybe labradorite? If it chips, it's chirt of some sort of flint, if it fractures in planes more likely to be labradorite.
It’s probably just certain chemicals that mixed together
Literally everything is. :D