Can you help? Blue / grey shale / slate with pyrite / sulfides

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Katazone, VIC
Found this today and wondering if anyone can give me info about it. Its layered dark and light, a thick 1cm wide layer of 1mm pyrite cubes visible along with thin lines of micro pyrite. Some of the dark lines are straight, some wavy ( these smaller lines are around or under 1mm )

After a pan and crush of a 2" chunk. See the sulfides / pyrite crystals and dust to the left. Lots.
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The bits I got
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Slate used to be clay,... that's what was used for damp course and roofing in the old days,.... that's if it is slate. :D
 
I think it's fairly common for slates that were laid down as clays with high organic content to turn into shales with high pyrite content. Not sure why, perhaps the organic matter was high in sulfur?
 
AtomRat said:
Ill define it a bit more - this isn't very common unless your on the gold here. Parks, you should know what I'm talking about

After working construction in that heat today, Parks brain no work. I'm still trying to comprehend the question.
 
I'll have a go.

Hold it like this
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There's the layers from oldest to newest on top with the crystals of organic poo poo on top. A common formation in ancient river beds caused by the slow erosion of host rock and organic material
 
the simple version = its old mud gone hard . that side of aust was under the sea a very long time ago . as the land rose it formed mud flats also dead sea life and vegetation sediments is part of the makeup . also that part of victoria was volcanic . so oil and coal and slates were formed during this upheaval .
 
Great answer stalker. Any clue as to why the pyrite is there? I do like the 'sulfer' content post above..that makes sense. Volcanic sulfur? Mixing with the dense red soils / clay here..hmm but these are now on top ( the red soils ...or its the other way around ) but I'm painting a picture now. The slate / shale also has oval whitish - grey blobs. Not sure what they are yet
 
Ohhh and Rivers with organic poo poo wasn't the answer. :( Funny I just call them rivers and don't look at it as sea.
 
The slate / shale also has oval whitish - grey blobs. Not sure what they are yet

Quartz. Its a crystal that grows in the gaps.
 
AtomRat said:
Woukd this slate be Ordovician or Silurian?

The one I was talking about is Lower Ordovician. Apparently a really early form of a plant that was one of the first. Looks like an alpine moss and is a seawater plant or seaweed called a graptolite. At least everyone should understand now why we get nice flat slate pavers, and talking about pavers I just thought of some on the footpath of a mining town that are huge pavers and have pyrites the size of marbles sticking out. I'll take a picture next week.

Graptolites
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It's strange to think that the quartz and sometimes gold moved into the gaps with the use of steam and grew there with microorganisms. When gold is found in this rock it comes through in streaks, like lightning. I've heard of mining companies loosing all their staff because they heard of streakers on the field and bought into another mining company that was doing so well that they didn't have to work anymore.
 
Wow so many smart people here who really know their stuff, totally impressed.
 
Wouldn't the grey blobs have been like pipe clay in their day(maybe). :)
 
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