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Identity Helpis it meteorite?

19th Aug 2010 18:10 UTCMartin Virt (2)

Hi there,

I hope someone help me with identification of this specimen found on the sidehill near Jilove u Decina in Czech republic. I found only this one. Its size is 30x15x12 cm, weigh is 4,2 kg, it has gray color,metallic gloss and is magnetic. Sorry for low quality of photos.

Martin Virt

19th Aug 2010 18:31 UTCRob Woodside 🌟 Manager

It looks like a slag with cubic or rhombohedral cleavage.

20th Aug 2010 00:08 UTCDon Saathoff Expert

It does not look like a meteorite.....large pegmatitic magnetite mass?

20th Aug 2010 00:11 UTCPavel Kartashov Manager

This isn't cleavage but skeletal crystals of some spinel-type phase. And it is a slag without any doubts.

20th Aug 2010 00:33 UTCRob Woodside 🌟 Manager

Right you are Pavel

20th Aug 2010 01:48 UTCEugene & Sharon Cisneros Expert

The crystals are definitely not octahedral, which rules out meteoritic material. If not convinced, grind and polish a small area and etch it with acid. You can find the directions on the internet. If an octahedral pattern appears, called Widmanstatten structure, you can be sure that it's a meteorite, as Iron-Nickel crystals are not formed on the earth. The lack of the Widmanstatten structure does not rule out that it is a meteorite however, as the crystals may be either too large or too small to be visible. Since all Iron-Nickel meteorites contain at least 4% Nickel, a test for Nickel would be useful in the determination. Of the hundreds of "meteorites" that have been presented to us for identification, only two were actually found to be meteorites. The term "meteorwrongs" has become an often used word in our vocabulary.

Gene

20th Aug 2010 09:55 UTCPavel Kartashov Manager

Dear Gene,

your etching method works only for significantly metallic meteorites. ;) This slag is mainly glass-oxide-silicate, may be with very minor metal drops in interstitions. No considerable nickel content presents in such slags because they forming during chromium production.

Pavel

20th Aug 2010 15:25 UTCMartin Virt (2)

I´m not glad hearin´ it. There is one strange thing around the slag. How could it appear in forest terrain about 5 mile away from the nearest town? May be a fragment of some historical ore processing? But thank you all with identification anyway.

20th Aug 2010 17:58 UTCEugene & Sharon Cisneros Expert

Pavel,

You are quite correct regarding metallic meteorites. The reason that I mentioned these tests is because the specimen in question is reportedly magnetic and I see what looks like a flattened spot in the third image. This could be flattened by testing for malleability, or it could be from grinding. Or, perhaps it's a natural feature, but it's difficult to tell from the image. Without having the specimen in hand, it's not possible to know density, hardness, malleability, degree of magnetism, etc. However, we do agree that it is definitely not a meteorite and that it is some type of smelter byproduct.

Gene

20th Aug 2010 23:51 UTCRonald John Gyllenhammer Expert

I agree with Rob and Pavel on slag. If so, it must have stayed hot for some time and probably cooled relatively slowly; not it's vesicular and shows some fairly well developed crystallization for slag.

27th Aug 2010 17:12 UTCUwe Kolitsch Manager

Yep, slag.

28th Aug 2010 10:04 UTCSebastian Möller Expert

Hello,

Definitely slag. Possibly the mineral is fayalite, one of the most common minerals from slag localities. Or some spinel phase.

Regards,

Sebastian Möller

28th Aug 2010 12:49 UTCMatteo Chinellato Expert

not meteorite, fusion slag

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