Trying to identify a weird metal found on a beach

In summary: Gold 19.3The density of the nugget is about 5.5 grams per cm3, which makes it about the same weight as lead.
  • #1
xtempore
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TL;DR Summary
This object was found on a New Zealand beach
IMG_20221220_171850.jpg

This object, about the size of a tennis ball was found by my brother. It's metal. It's very hard. Cannot scratch it with a Stanley knife. Cannot break even a small piece off using pliers. Thrown with force at concrete and undamaged. Relatively heavy. My brother estimates similar weight to lead.
Any ideas what it is, OR how to test it?
 
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  • #2
That looks like a rare lump of osmiridium or iridosmine, an alloy of osmium and iridium. If it was, it would be worth about US$400 per oz, maybe much more to a collector of mineral specimens.
https://en.wikipedia.org/wiki/Osmiridium

To identify osmiridium in the field, hit a bead with a big hammer. If the hammer head breaks, you know that it is good.

Take it to a place that has an XRF, maybe a geology department at a university, or a metal scrap recycler that sorts and supplies a local foundry.

Let us know what it turns out to be.
 
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  • #3
Can you determine the density by weighing it and determining its volume using the water displacement method? That would narrow it down pretty quickly.
 
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  • #4
Baluncore said:
If it was, it would be worth about US$400 per oz
Maybe he should stop hitting it with stuff then? :wink:
 
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  • #5
berkeman said:
Maybe he should stop hitting it with stuff then?
Yes.
It would be interesting to know the geology of the hill behind the beach. The path taken for a hard and heavy native metal nugget to reach the beach would suggest gold panning for other heavy native metals, some of which are even more valuable.

What was the latitude and longitude of the find?
Has there been any alluvial mining of metals in the area?
Was it a rocky beach with a steep, eroding cliff?
Could the nugget have been transported from afar by glaciation?

Iridium makes the best reflectors. Has a lighthouse above the beach ever burned down?
 
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  • #6
Maybe chromium?
 
  • #7
A quick Google images search suggests, if it's a natural nugget, it's likely not Osmiridum or Iridosmine - they don't seem to form bubble-like shapes:

1671574167969.png
But Hematite does:
1671574120861.png

Though it's density is even less than iron.
 
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  • #8
It looks a like iron formed by the Thermit process, maybe when welding railway lines or big cables.
 
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  • #9
Wouldn't it be rusty? (I honestly have no idea....)
 
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  • #10
The iron from Thermit does look exactly like the picture, but you must be correct about rust.
 
  • #11
I'll vote for botryoidal goethite or hematite cluster. The other suggestions are much more rare than iron oxides. "When you hear hoof beats, think of horses, not zebras."

Google says hematite isn't magnetic unless heated. The iron from thermite would be. You should be able to scratch it with quartz. Also a red/brown streak test would help. There's lots of mineral id sites on the web. Here's one I picked at random. https://geology.com/minerals/hemati...tremely variable,fibrous, oolitic, and others.
You might consider selling it instead of trying to ruin it. It's a spectacular specimen.
 
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  • #12
It's a pity the author is not following up.

"It looks like kryptonite" is all we can do from a photo. Obviously not so useful. The density, on the other hand, would tell us something. ("Similar weight to lead" is not so helpful - lead is 11, and brass is 9. Looks similar to me. And steel is 8) As would the hardness in a more quantitative way. (Steels are still an option) Maybe where it was found - just down the beach from "Billy Bob's Tungsten Emporium" would be useful to know..
 
  • #13
@xtempore If we knew the nearest city location of the specimen now, we could arrange an XRF, which for heavy metals would be very satisfying and conclusive.

If we knew the geographic location (lat,lng) of the find from Google Earth, we could assess the geological possibilities.
 
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  • #15
Borg said:
I did a Google image search and the most similar images were listed as nickel.
xtempore said:
Cannot scratch it with a Stanley knife.
Nickel is softer than a hardened carbon steel knife blade.
 
  • #16
Baluncore said:
Nickel is softer than a hardened carbon steel knife blade.
I saw that he couldn't scratch it but I wondered if the effort he put into it was equivalent to his effort to follow-up on the thread.
 
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  • #17
The OP fooled us all. He hasn't been here since he posted his question.
We can guess, but any guesss that requires OP feedback isn't going anywhere.
 
  • #18
You could narrow the options by measuring the density. Weigh the object then get a large measuring jug graduated in ml or cm3. Put enough water in the jug so that when you put the object in it will be completely submerged but the jug does not overflow. Measure carefully the before and after volumes. The difference is the volume of the object. (Good old Archimedes). Then divide the weight in grams by the volume in cm3.
Densities of some common metals are:
Iron 7.85 g/cm3
Copper 8.94 ( I know it doesn't look like copper)
Silver 10.5 but too soft
Gold a whopping 19.3 but too soft
Tungsten also 19.3 and hard.
 
  • #19
Ah, so sorry for the lack of reply! I thought I'd get an email notification when someone commented. :/

Anyway, just got an update from my brother. He says it IS magnetic (as in a magnet is attracted to it).

I thought about using Archimedes test as well, but I don't have direct access to it. My brother's not very technically reminded, and I don't think he'd have an accurate scale to measure it.

From what I understand, it was near Marfell's Beach (-41.72433988098268, 174.20280210352044). To the best of my knowledge there isn't and has never been any mining around that area. There is a salt-works.

The rail-line is probably too far inland from the beach to be related.

Hoping to get access to it next time he comes for a visit!
 
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  • #20
If it is magnetic, it is likely some sort of steel slag.
 
  • #21
xtempore said:
near Marfell's Beach (-41.72433988098268, 174.20280210352044).
Can you be a little more specific? 14 decimals only narrows it down to tens of nanometers.

:oldbiggrin:
 
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  • #22
Lol. Yeah, just a lazy copy paste from Google Maps. ;)
 
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  • #23
Perhaps we should excoriate someone at Google Maps. Or marvel at our capabilities for global location........
 
  • #24
Google Map link, if I got those numbers right

Nothing suspicious there, as far as I can see.

Google gives back some similar pictures for 'nickel nodule'?
 
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  • #27
DaveC426913 said:
Nice likeness, but didn't we establish that nickel is too soft to resist being nicked?
I thought so too. I'm working with second-hand information from my brother. Nickel does have a Mohs hardness of 4 though. So it's about the same as steel. Give the shape of the nodules it'd be hard to really exert a good pressure with the blade, and given that they are of roughly equal hardness, maybe it's not going to be enough to scratch it noticeably.

Could the fact that this grows like a crystal mean it also has a greater degree of hardness when compared to ordinary nickel?
 
  • #28
xtempore said:
Could the fact that this grows like a crystal mean it also has a greater degree of hardness when compared to ordinary nickel?
Electro-deposited nickel tends to have voids, so I would expect it to be softer than a crystal grown slowly.

Compounds of nickel that form on, and protect the surface, may be many times harder than the native nickel metal.
 
  • #29
xtempore said:
So it's about the same as steel.
Hardened( 7) or mild steel( 4.5 )?
a jacknife blade should scratch the surface.
 
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1. What are the characteristics of the metal found on the beach?

The characteristics of the metal found on the beach can vary depending on its composition and exposure to the elements. It may have a unique color, texture, or weight compared to other metals. It may also have rust or corrosion, which can provide clues about its age and origin.

2. How can I determine the type of metal found on the beach?

To determine the type of metal found on the beach, you can use a variety of methods such as visual inspection, magnetism, and chemical tests. Visual inspection can give you an idea of the metal's color, texture, and weight. Magnetism can help identify if the metal is ferrous or non-ferrous. Chemical tests, such as the acid test, can be used to identify specific types of metals.

3. Is the metal found on the beach valuable?

The value of the metal found on the beach depends on its type, condition, and rarity. Some metals, such as gold and silver, are more valuable than others. However, even common metals can have value if they are in good condition or have historical significance. It is best to consult with a professional appraiser or metal specialist to determine the value of the metal.

4. Could the metal found on the beach be hazardous?

It is possible that the metal found on the beach could be hazardous. Some metals, such as lead and mercury, can be toxic if ingested or inhaled. It is important to handle the metal with caution and avoid direct contact if possible. If you are unsure about the safety of the metal, it is best to contact a local environmental agency for guidance.

5. What should I do with the metal found on the beach?

If you have identified the metal and determined that it is not hazardous, you can decide what to do with it. Some options include keeping it as a souvenir, selling it for scrap, or donating it to a museum or historical society. If you are unsure about the value or significance of the metal, it is best to seek the advice of a professional before making a decision.

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