What kind of rock is this?

Found this specimen at a beach in Adelaide. Detected very easy, down about 30 cm. Its around 4 inches long in the old scale and would weigh about 350 grams comparing it to a tin of food. Magnets are only barely attracted to it. A tiny magnet will stick to it but a powerful pot magnet will fall off. Maybe slag? I've heard of Ironstone but never seen any?. Any help would be appreciated. TT

After closer inspection last night it weighs 550 grams

You have me stumped! I'm sure someone on here will know.

TTKooAu said:

Found this specimen at a beach in Adelaide. Detected very easy, down about 30 cm. Its around 4 inches long in the old scale and would weigh about 350 grams comparing it to a tin of food. Magnets are only barely attracted to it. A tiny magnet will stick to it but a powerful pot magnet will fall off. Maybe slag? I've heard of Ironstone but never seen any?. Any help would be appreciated. TT

https://www.prospectingaustralia.com/forum/img/member-images/1600/1395293029_rock1.jpg
https://www.prospectingaustralia.com/forum/img/member-images/1600/1395293093_rock_2.jpg
https://www.prospectingaustralia.com/forum/img/member-images/1600/1395293119_rock3.jpg

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type in 'mineral identification' a to z on the tube!

that is a real weird looking rock, almost like it's got some fossilized pieces to it

i was looking at a periodic table and there are some stones 83 etc that are slightly magnetic in this section of the table. perhaps one of those. Bismuth being one.

May have fallen from space ?

Ozjono said:

May have fallen from space ?

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I thought that at first, the section that looks melted, but the rest of the rock just looks like a rock!

it could be impactite not correct spelling fused crust after impact maybe

Try and have a look at the texture of the rock, a loupe or magnifying glass would be handy.
Are there any visible grains or crystals ?
Meteorites will normally exhibit more rounded features externally where it has burnt up entering the atmosphere.
A couple of bits allmost look glassy, makes me think maybe volcanic.... but i could be way off the mark.

looks like rock with fossils has been melted some how an impact can melt the rock it hits just a guess some impacts can be hotter than nukes

Could be a type of sphalerite ore. It's appearance can vary greatly, but it has a high iron content ( to sound of your detector ) is known in that area and forms with slightly magnetic impurities.
Very hard to identify anything from a photo though, do the usual identification steps the other guys have mentioned.

DD

G'Day

Its hard to tell without handling the thing. As a guess I would plum for hematite. It is very slightly magnetic as some higher grade hematite can be but not as much as magnetite. There are lots of hematite bearing rocks around Adelaide but you would have to ask yourself how such a heavy rock got in amongst beach sand - or was it in the rocky parts?. Some types of hematite are shiny and bright (called specular hematite or specularite) and can form what is called a botryoidal texture. This looks like smooth bubbbles on the surface and when you break into the bubbles or see them on their edge they appear like very fine radiating crystals. One photo seemed to have that appearance.

Araluen

shivan said:

Try and have a look at the texture of the rock, a loupe or magnifying glass would be handy.
Are there any visible grains or crystals ?
Meteorites will normally exhibit more rounded features externally where it has burnt up entering the atmosphere.
A couple of bits allmost look glassy, makes me think maybe volcanic.... but i could be way off the mark.

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Took these shots through the loupe. They show the grain, similar to iron filing on a magnet. I'm going to take it to the Museum in Adelaide, they should have an idea


.

Some more shots




Thanks to all for your help, appreciated. TT

I would find your local gem club and ask them, and then let me know

We would all like to know what it is... please find out and let the rest of us know as well..

Ok, will keep you posted, cheers
TT

It looks to me to be a nickel iron meteor fragment, very similar crystalline shapes boundaries to two small ones I found here in Qld.
The ones I had ( only have half of one left as I didn't know what they were at the time of finding) was very similar on the "incoming" side and appeared to have been slightly melted, on the reverse of that piece the structure was triangular hopper crystal structure.

Not knowing what they were I smashed one with a hammer and it broke in two, the appearance on the inside was exactly the same as the "grainy" side of yours.

My pieces were more brassy coloured and were found on a beach in salty water.
The amount of nickel would probably inhibit the magnet's influence.

I had a third I had been given by an opal miner as past of a rough parcel of boulder opal, it was very similar and weighed about 250 to 300 grams, was fully intact. It looked much like yours but was very heavy for it's size.
I forgot it was an the bucket and sold the opal along with the meteorite for three hundred dollars to a man that was desperate for some opal specimens , been kicking myself ever since. :8

I still have the small half piece ...somewhere.

I'm also guessing meteor, even if its not its a cool find