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Good luck over there! The traces look promising. Nice to see a bit of red colour kicking about. :cool:

It's always interesting to see the similarities between opal fields.

We generally don't see opal too often in those upper dry strata level layers as it's more concentrated in the opal clay levels under the overlying sandstones, but it certainly does happen here and there.

The purple and mustard coloured staining (bottom pic) is very common here also. It's due to chemical leaching from hydrothermal venting taking place in the former shallow sedimentary deposits. We see that commonly here at the Ridge where there's only a single level lens present. It will also permeate softer clays underneath a good level and can be quite wet and puggy at times, unlike the upper layers nearer the surface where it will be quite hard and dry. We call it a "dry mustard level".

Looking forward to seeing more pics.
Keep up the great work and stay safe 20x!

Cheers,
Shauno.
 
Syndyne said:
Good luck over there! The traces look promising. Nice to see a bit of red colour kicking about. :cool:

It's always interesting to see the similarities between opal fields.

We generally don't see opal too often in those upper dry strata level layers as it's more concentrated in the opal clay levels under the overlying sandstones, but it certainly does happen here and there.

The purple and mustard coloured staining (bottom pic) is very common here also. It's due to chemical leaching from hydrothermal venting taking place in the former shallow sedimentary deposits. We see that commonly here at the Ridge where there's only a single level lens present. It will also permeate softer clays underneath a good level and can be quite wet and puggy at times, unlike the upper layers nearer the surface where it will be quite hard and dry. We call it a "dry mustard level".

Looking forward to seeing more pics.
Keep up the great work and stay safe 20x!

Cheers,
Shauno.
How interesting, Ive actually watched heaps of doco's on hydrothermal vents and discovery's of the abyss. Just 2 nights ago I watched another on the Mariana trench.
I knew this area is ancient sea floor but never actually put it all together like you have.
Thanks heaps for your input as it's much appreciated.
I'm re-assessing..
Scott :cool:
 
You're always welcome, Scott.

Great to hear things are clicking for you! That's the reason we see a lot of marine life that's been opalised. We also find water still stuck inside cavities in nobbies on occasion that is highly salty to the taste.

It's often forgotten, or is simply the last thing on your mind that you're working in ancient shallow seabeds and onto the surrounding areas that would've been partial coastal inlets and almost tropical in nature. There's a lot of interplay between the kaolin clays and the successive sandstone sedimentary layers to do with heavy geologic movement and changes like earthquakes, erosion, droughts, floods etc. over the period the opal was forming during the early cretaceous period. Australia was only just breaking away from the other continents at that point also.

This is where the required heat, pressure, electricity and time come from that arranged and settled the Silica molecules in a way that gives us potch and precious opal along with the endless unique colour patterns. Once it had leached into the voids and cavities that were left over by either fossil deposition or possible gaseous/thermal voids -in our case here with the nobby and seam opal fields- add those specific actions over time and gem opal is the end result.

Some of the faults (or steps in the level/roof) we come across in opal bearing areas here are huge and can run for many hundreds of metres through fields. I've never seen opal form without them or, blows (breccia pipes or ancient geothermal vents) present. There must've been some major quakes back then as the ground has moved and displaced up to twenty feet or more in places. It can make working a claim quite tricky to say the least!

Of course that certainly may be somewhat different where you're working over there, but I'd almost bet that you'll notice similar things here and there and various commonalities while digging through the country now. It can be quite a different story when it comes to actually reading the ground. That takes years and years to build a decent knowledge base as it's not so consistent given the multitude of places we can find opal outside of the proper opal clay levels, such as the shallow sub-surface layers (we call biscuit band), or even just a thin horizontal carrying band or slide up in the sandstone roof at times -often for no real obvious reason.

It's always been such a hit and miss thing. You can come to opal country completely green, throw four pegs in pretty blindly, sink a hole and hit the jackpot, or like us, have all the knowledge in the world about opal and go from claim to claim for decade after decade and have very little luck. Like they say: "Some are born lucky and some are lucky to be born". That's pretty right too I reckon. :lol:

Food for thought anyhow. Always feel free to sing out if there's anything you can't get your head around. Remember to dig any and all fossils out very gently! You never know if you'll find one that will potentially alter known history (as we did here in the 80's).

All the best and kindest regards,
Shauno.
 
Big things have small beginnings don't they :lol: :cool: ..
1626248295_img_20210714_173424.jpg

1626248325_img_20210714_173433.jpg
 
Mackka said:
Say what?
Mackka
Opal mining mainly consists of pouring energy time and money down a hole mate.
I dug the shaft to keep my mind off drinking and smoking and that's all.
The old man has predictably taken over and getting nothing ?
Opal will never give me a fever, I'm a gold prospector!!
 

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