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[robotunicorn]

I found two similar pieces like this in the same area while metal detecting in Spain.

 

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[Red-Coat]

What leads you to believe it's a meteorite?

 

[robotunicorn]

I’ve done all the tests I could do myself, magnet, streak test, nickel test and I looked at it under a microscope. I know it’s not hematite or slag.

 

[jcc]

Here are some meteorite samples, upper left is two unclassified NWA's, the tektite is not a meteorite but formed from earth materials during a meteor impact.

 

[Red-Coat]

I’ve done all the tests I could do myself, magnet, streak test, nickel test and I looked at it under a microscope. I know it’s not hematite or slag.

OK... but what were the results?

Strength of magnetism... colour, nature and difficulty of streak... positive for nickel at what sensitivity of testing, or a true quantitative result... what did you think you see under the microscope as features characteristic of meteorites?

 

[robotunicorn]

What’s that metallic one upper right ? Both mine look very similar on one of the sides. Smaller pieces of tektite was also found close to were I found them.

 

[robotunicorn]

OK... but what were the results?

Strength of magnetism... colour, nature and difficulty of streak... positive for nickel at what sensitivity of testing, or a true quantitative result... what did you think you see under the microscope as features characteristic of meteorites?

They’re not super magnetic, but a strong magnet will stick to them. I did a streak test on 4 different ceramic tiles/surfaces and on 3 of them, it just scratched the tile without leaving any mark, but on the 4th one it left a faint gray streak. I only checked if it contains nickel, with a nickel tester. Not a fancy machine or anything like that. When I looked under the microscope, I could see lots of crystal-like particles and chondrules.

 

[jcc]

What’s that metallic one upper right ? Both mine look very similar on one of the sides. Smaller pieces of tektite was also found close to were I found them.

Campo del Cielo from Chaco, Argentina. Probably the easiest large impact Meteorite sample to obtain. Look at Wikipedia for the usual info.

 

[Red-Coat]

What’s that metallic one upper right ? Both mine look very similar on one of the sides. Smaller pieces of tektite was also found close to were I found them.

They’re not super magnetic, but a strong magnet will stick to them. I did a streak test on 4 different ceramic tiles/surfaces and on 3 of them, it just scratched the tile without leaving any mark, but on the 4th one it left a faint gray streak. I only checked if it contains nickel, with a nickel tester. Not a fancy machine or anything like that. When I looked under the microscope, I could see lots of crystal-like particles and chondrules.

If you mean the one labelled ‘Campo del Cielo’, that’s a Coarse Octahedrite-Hexahedrite assigned to the IAB Main Group of nickel-iron meteorites. It contains roughly 90% iron and so is very strongly attracted to a magnet. The high iron content makes it very prone to rusting, and the specimen you pictured would not have had that appearance when found. It has been tumbled to remove the rust. Smaller Campo del Cielo specimens reaching the collector market are also routinely the result of a larger specimen being dipped in liquid nitrogen and hit with a hammer to break them down into smaller clusters with a crystalline metallic appearance. Meteorites of this type (nickel-irons) do not exhibit chondrules in their matrix.

If you used a nickel testing kit (as used to assist those who are allergic to nickel), those are typically sensitive to between 10-15ppm of nickel and will give a positive result on a wide variety of materials, whether meteoritic or not (Campo del Cielo typically contains around 10% nickel).

You say that “Smaller pieces of tektite was also found close to where I found them” but there’s no logic in that. Tektites are not usually found in association with meteorites since the size of impact needed to create them results in them being ejected far away from the impact site. Tektites also have a very specific set of strewnfield areas relating to very large impacts. You also said “Found in Andalusia, Spain” on your other post, but no tektites have been found in Spain since it hasn’t been the location of any such impacts. The craters and impact sites from which tektites have been ejected are also ancient, such that iron meteorites associated with such sites would be severely rusted. You didn’t picture the claimed tektite pieces, but I suspect they are not what you believe them to be.

The streak tests are inconclusive.

But the clincher is this. Anything with has a metallic appearance or a substantially metallic composition which exhibits anything other than very strong attraction to a magnet will not be meteorite. There are no exceptions to that rule.

 

[jcc]

If you Google "First possible meteorite crater in Spain is discovered in Andalucía" there is a news article describing a 4 km diameter, 1000 meter deep, crater with 20 km rim.

I don't claim extensive knowledge, I just have a few under $25 samples that were interesting me.

 

[Red-Coat]

If you Google "First possible meteorite crater in Spain is discovered in Andalucía" there is a news article describing a 4 km diameter, 1000 meter deep, crater with 20 km rim.

The claim currently for the Almeria structure is that it’s a “probable” impact crater. It is however unconfirmed and contentious. The evidence from a polymict breccia clast and three quartz grains with weak PDF is not supported by other aspects in that there is no observed crystallographic orientation or shock metamorphism. Also there is no characteristic evidence of shatter cones, impact melt, impact glass or ejecta deposits, and no known tektites associated with a possible impact. The structure is at least 5 million years old (believed by the proponent authors to be 8 million years old) and so (if it is an impact crater) anything nickel-iron would be severely rusted if it has survived in at all.

Spain has two other contentious claimed impact structures, both in Aragon: the Rubielos de la Cérida structure is 20-40 million years old, but the majority of scientists and the mainstream consensus is that it’s a non-impact related tectonic feature; and the Azuara structure which is between 32-40 millon years old and formerly listed in the Earth Impact Database but subsequently removed following rejection of the claims that it was impact-related.

 

[robotunicorn]

I’m sorry but what? So according to you, all tektite found in Spain is fake ? I refuse to believe so. Multiple meteorites have struck the ground fairly close to where my house is located. There is even a map that will show you locations. A simple google search will show you. If you really could not tell, I have obviously polished it and removed all the rust.