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Meteorwrong?

bernie_UK

By bernie_UK
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bernie_UK

bernie_UK

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I've been fortunate, as a long-distance truck driver, to have witnessed 2 fireball trails, ( space junk ? ), and many meteorite trails over the years on my travels around Europe- the most spectacular over Eyemouth UK, many years ago. Anyway, I've been using a heavy-for-size 'cinder' as a paper weight for a couple of years since finding it in Norfolk during a walk; never bothering to really examine it. It's just weird-looking and different so I picked it up and kept it .The other day it got scratched and noticed that it's green rock under the burnt appearance. ... Decided it has to be 'kryptonite' !. - Well it'll be something simple but it isn't magnetic ,post-26024-0-17199900-1347740373_thumb.jpost-26024-0-47687800-1347740667_thumb.j. ( I've sent 360 deg. videos of it off to Durham Uni and NHM to confirm it as terrestrial or a product of man )... post-26024-0-10745200-1347740261_thumb.j. Anyway, attached a couple of views for general interest as meteor 'rights' and wrongs are of general interest.

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bernie_UK

bernie_UK

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post-26024-0-73855000-1347747509_thumb.jpost-26024-0-47028200-1347747555_thumb.j

Thanks for the 'welcomes' and replies. It weighs1.3lbs and I found it on a shingle beach a couple of miles from the nearest village, no old lime kilns nearby to my knowledge but ships have crashed quite a bit and wars have blown a few apart so your furnace junk idea can't be ruled out. Quite likely in fact. but wouldn't it give a nice feeling to discover it was a chipping off one of our 'cousins'. A really strong magnate has no effect on it and I must say I'm intrigued by the olive-green colour just beneath the blackened hard surface. ...dream on eh !

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John

John

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Welcome to SGL :smiley:

Green is a very unusual colour for a meteorite. The only one I know of is called Tatahouine and fell in Tunisia in June 1931. Many (but not all) meteorites do respond to a magnet as they have varying %'s of nickel-iron in them.

It will be interesting to see what the NHM make of it.

Tatahouine specimens retail for around $20 per gram by the way. Lunar and Martian specimens around $500-$1000 or more per gram.

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bernie_UK

bernie_UK

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Thanks to all again for the 'welcomes' to SGL... a brilliant info forum and especially the stunning astro photos. Wonderful.

On the more mundane subject of my Norfolk 'cinder', I've surfed the web on 'meteorwrong' ID help sites and the facts ;- non magnetic and green - don't bode well. Apart from bits blown off 4 Vesta and found in 1931, which are as rare as the proverbial rocking horse doodoo. Green, non-magnetic , doesn't match the usual meteorite-find profile.

So, I scraped a few more parts of it and just literally a scratch under the dark exterior it's definately a regular continuous green all over. ? Looking at Copper ore on the web it seems to be a more translucient green with a 'minerally' texture and not usually found on a beach - one rock. My rock is a matt and has a smooth texture.

Shame I missed the open-house ' bring-along-your-meteorite-day' at the NHM on 2nd September.post-26024-0-57602200-1347909451_thumb.j. Just have to see what the experts reckon from my email.

I've probably listened to 'Journey into space' and read Dan Dare comics too much as a kid !!

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bernie_UK

bernie_UK

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Well- here's the result from the very polite and knowledgeable curator of minerals at NHM , Mr. Peter Tandy and grateful thanks to him ;-

".........Thank you for your enquiry, which has been passed to me as I deal with public mineral enquiries.

It is not our preference to try and make mineral identifications from images alone, as they can never fully substitute for the look and feel of the real item. However, they can be a useful first step in some circumstances.

Having looked at the images which you sent, I am afraid that I shall add one more to the number of meteo-wrongs which you found, and which I get sent every year as enquiries. What you have is certainly not a meteorite. In fact it doesn’t resemble a meteorite at all. Meteorites are broadly divided into 2 groups, the irons and the stones. This clearly isn’t an iron, as they resemble pieces of scrap iron, and this doesn’t look like that, and isn’t metallic. The stones are characterized by showing a black glassy fusion crust on outer surfaces. This is generated when the stone enters the atmosphere and is heated to red/white heat. As it does so, the outer crust melts but only to s depth of 1mm or less. This is because the stone has been in space for 4 billion years or so, at a temperature close to absolute zero, so it would take a lot to heat it up. As rock is a poor conductor of heat, the few seconds it takes to pass through the atmosphere isn’t enough time to heat it. As it loses velocity, so it loses heat, and he molten outer crust solidifies rapidly. When a melt is cooled rapidly, it forma s a glass as the atoms have no time to order themselves. Your specimen shows no such crust. I know it is black and you say the black can be scraped off, but it still isn’t a meteoritic fusion crust.

In addition, your specimen is too angular. As the outer surface melts, the first areas to burn away are any points which stick out. So stony meteorites are essentially smooth, but may still have an irregular outline. Also, you mention that it has no magnetic attraction, and most meteorites (all irons and most stones) are attracted to a magnet. Attraction is not a guarantee of a meteorite, but non-attraction is almost a guarantee that it isn’t one.

Finally, your specimen shows a number of gas bubble cavities. This is not a characteristic of meteorites, as they are primitive rocks which have not been melted in that way.

You can try getting a rough (very rough) indication of its density if you measure its volume (in cubic centimeters) and divide that into its weight (in grams). Working out the volume of an irregularly shaped solid is not easy, but a rough estimate can be gained by measuring its length, breadth and depth, or better still, but displacing water in a measuring jug. Make a note of how much water is in the jug to start with, then make sure the stone is completely immersed in it, and note the new measure. By subtraction you can get a reasonable estimate of the volume. Note though. If you are to use a jug straight from the kitchen, make sure you get permission first…….!!! Stony meteorites have a density of about 3.3 or so, iron ones about 7.0-8.0.

Your specimen also does not resemble anything natural, and is almost certainly is a piece of industrial waste from some process (probably steel or iron making), or as you said, from a boiler or furnace. It may have ended up on the beach as a piece of ship’s ballast, lost either when the ballast was ‘flushed’ or from a wrecked ship. Or it may have been brought into the area originally as road or track fill – sadly we shall probably never know.

I hope this is of help and interest to you.

Yours sincerely

Peter Tandy

(Curator:Minerals)

...... so for all of us intrigued by the open skys under which we marvel, a very helpful, expert and salient insight into my ' meteorwrong '......but a very faithful paperweight 'wannabe'..........

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