STONE ?

[joao garimpeiro]

I found this rock on gold mining. Someone can tell me what it is? I do not know this kind of rock.

 

[silver]

certainly is different Joao.

 

[k man]

Maybe a fosilized peach?

 

[blisters]

My first impression was fornicaceous rockus, but since I suck at seeing much definition in online photos I'd say you have a piece of calcrete.
Jon

 

[silver]

Or even a Bunya nut !

 

[joao garimpeiro]

Hi Silver,

It is very strange this rock. I wonder what it is? :|

 

[joao garimpeiro]

Maybe a fosilized peach?

Hi K man,

It is a rock inside the other. looks like a peach even

It will be a fossil?

 

[silver]

Almost looks like an Ochre centre piece from here.

 

[silver]

Must have fell into salt water and got silted over, and as the silt hardened there was a cavity left around it(because it got smaller over time), salt water sucks moisture out of things(potato experiment), so my guess is that it definately used to be organic before it got turned into stone.

 

[joao garimpeiro]

My first impression was fornicaceous rockus, but since I suck at seeing much definition in online photos I'd say you have a piece of calcrete.
Jon

Thank you Jon

I had never found anything like this!

 

[joao garimpeiro]

Must have fell into salt water and got silted over, and as the silt hardened there was a cavity left around it(because it got smaller over time), salt water sucks moisture out of things(potato experiment), so my guess is that it definately used to be organic before it got turned into stone.

Thank you Silver,

this rock is very light. the white part seems limestone

 

[blisters]

If you bust the centre stone I'd bet it would be white inside. It looks chalky and is layered like an onion and light red/brown layer so my guess is a calcrete nodule plus it's light.
Jon

 

[silver]

So how is calcrete formed, and what is it Jon ? :|

If you bust the centre stone I'd bet it would be white inside. It looks chalky and is layered like an onion and light red/brown layer so my guess is a calcrete nodule plus it's light.
Jon

 

[blisters]

Silver, calcrete forms from the leaching of carbonates from surface soils which perculates downwards and the carbonates precipitate out of solution. The carbonates could come from sand etc. I have seen a fair bit of this in WA unless I miss ID'd the rock. The nodules would form like a pearl. My geology memory is fairly distant these days but I think climatic conditions also come into effect as it must be dry enough that there is not too much water to put the precipitated carbonate back into solution.
Jon

 

[AtomRat]

There's some of these at the gemclub, I'll go and see what info I can find for you mate

 

[blisters]

Scratch it and test with acid it should bubble if calcrete. If it doesn't then maybe it's a geode. Calcrete would be a significant size deposit as well sothere should be a lot more around.
Jon

 

[joao garimpeiro]

There's some of these at the gemclub, I'll go and see what info I can find for you mate

Thank you mate!

 

[silver]

We'll all get to the bottom of it Joao, one way or another.... Australian Mineralogical International Rescue Team (AMIRT) to the rescue.

 

[joao garimpeiro]

We'll all get to the bottom of it Joao, one way or another.... Australian Mineralogical International Rescue Team (AMIRT) to the rescue.

I love you guys!

 

[Ditherer and Son]

Definitely a fossilised hotdog