Meteorite?
I’ve been saving this rock for a later post. But complications have made it impossible for me to examine the rock up close any time soon. All I have are these older photos below. So I can just write about it now I guess, it wont matter if I wait any longer.
It’s (supposedly) not magnetic (that rules out iron slag right?). It (supposedly) weighs about 1-2 kilos. Its about 15x10x10 cm in size. (reduced size on the photos)
I sent the photos to an geology expert a couple of years ago, before studying geology myself in the hopes of helping my (now sadly enough dead) friend in helping to identify it.
The expert just replied shortly and claimed that it “most definitely was a conglomerate”.
Im no expert, just a first year student. An amateur. But this doesn’t look like any conglomerate that I know of. Where are the pieces of rocks and granules? Shouldn’t there be at least one lousy piece of granule visible if the craters are the sockets of rocks? Are they really all loosened and gone? Doesnt sound very plaucible to me. And when I replied to the experts answer with a follow up queastion and asked how this could be a conglomerate without any visible captured parts, his stuck up pride probably got offended and he just got bored with me and didnt answer at all. I almost lost all faith in geologists that time. What an idiot. Esteemed professor emeritus of Lund university and all. Well, he didnt make that far in the academical world on being friendly to the taxpayers who payed him and his research (Publically funded universities in Sweden you know). Well enough about him.
In my, very unprofessional opinion, this looks much more like a meteorite. But according to the expert, that wasnt even an option. I really never understood why.
I know that meteorites of course are less likely to be found in comparison to just about any type of rock. I’m not stupid on that part. But I can’t get over the fact that it looks like one much more than it looks like a conglomerate.
The rock also comes with a story (from my dead friend) that his father actually saw “a falling star” and went looking in the direction of where it seemed to have fell. Some miles away he found burned grass and this piece of rock between some cliffs at the west coast of Sweden. Around 1920 I think he said this all took place.
What does my readers say? Conglomerate? Meteorite? Iron slag? Flint? Or something else? What can you make of it just by looking at these photos (that’s all I have, its impossible for me to examine the rock itself or take better photos any time soon). Im all ears.
June 1, 2008 + Posted in Mineralogy, Petrology +
Sorry - definitely not a meteorite! Obviously a soft rock, judging from the erosion gouges. (Definitely not fusion crust)
I’m not a geologist (amateur rock and meteorite collector) but perhaps the conglomeration was suspected from the soft areas vs harder?
Meteorites - “stonys”, and even some Martian, are magnetic in varying degrees due to the iron and/or nickle content.
Have a look here: http://www.meteorites.wustl.edu/what_to_do.htm
-Among the most educational for learning about meteorites.
Cool looking rock, just the same.
Regards,
Joe
Comment by Joe — June 1, 2008 @ 6:51 pm
I am requesting a post on the work market situation for geologists, in Sweden and abroad, since this would be a major factor in deciding to study the subject. Get writing!
Comment by Trogen läsare — June 1, 2008 @ 7:01 pm
Joe: Thanks for your answer. Not at all convinced about it being anything at all yet. But a conglomerate is still nothing I believe in without much more proof.
Trogen: Will do.
Comment by Antimonite — June 1, 2008 @ 9:14 pm
It looks like a limestone. Does it fizz?
Comment by Lab Lemming — June 1, 2008 @ 10:54 pm
In the first picture there seem to be lots of regmaglypts in the rock!
Compare with this picture! http://www.flickr.com/photos/86624586@N00/11313160/
“Campo del Cielo iron meteorite, well regmaglypted, 70 kg.”
.
I’m a complete amateur, but I think there is something that resembles fusion crust (between the regmaglypts) in the fourth picture.
Comment by Mikah — June 2, 2008 @ 12:02 am
Lab: Dont know and cannot test.
Comment by Antimonite — June 2, 2008 @ 11:02 am
Vesicular basalt perhaps?
Comment by Antimonite — June 2, 2008 @ 11:14 am
First let us know about the density of this rock. An iron meteorite is going to weight a lot (based on the sizes you gave, 10kg if it is completely made of iron : density = 7,87 g/cm³)
No matter what it is, the surface is eroded.
Also, I’ve observed this same pattern on sandstones and limestones that are or were on cliffs, sometimes a kilometer of distance from the sea. This pattern was explained by erosion due to “seawater spray” (in french it is called “embruns”)
Some organisms are able to completely perforate any sedimentary rocks, as seen in paleo-beachrocks. They pass trough shells, rocks, cements etc… But this rock would have sheltered a big familly
Not sur about the conglomerate origin. Some conglomerate have a lot of matrix compared to clasts but as the hole aren’t connected, it calls for a rapid and intense “cementation”, before the compaction which is still possible but in particular diagenetic environnements.
The only way to have more information would be to break the rock in 2 to see if :
* there are undisolved clasts
* the holes are only at the surface ==> erosion process
* if you break you arm trying to split it in two, this is maybe an iron meteorite
Hope it helps a bit!
Valentin
Comment by Valentin — June 2, 2008 @ 12:47 pm
Valentin: If I ever get my hands on the rock again I will test. Probably not break it in half, but at least look at it more closely to see what type of mineral its composed of.
Your explanations on the conglomerate origin and erosional process sounds very plaucibel. I appreciate the information!
Comment by Antimonite — June 2, 2008 @ 1:01 pm
The pits could be confused with regmaglypts, but they certainly look erosional. I’ve seen erosion like this on a limestone near the base of a cliff before, I imagine because of rainwater falling off the cliff onto the rock. Just because it is very eroded does not mean that it is not a meteorite (search for pics of the famous Willamette meteorite).
Also, just because it does not attract a magnet does not mean it is not a meteorite (see achondrites).
The striations that run _into_ the pits certainly look sedimentary (shows up well in the bottom photo). A stony meteorite would not have that type of feature. A meteorite could have something like that occur with terrestrial processes, but on this rock they appear to be more than just surface features - as in sedimentary bedding.
I think it’s sedimentary. I’m a first-year geology student as well.
However, also a meteorite enthusiast. Cool rock, though.
Comment by bryan — June 2, 2008 @ 2:26 pm