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 Post subject: Re: Springsure labradorite
PostPosted: Thu Jul 14, 2016 7:44 am 
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Seems to shift depending on the light source and intensity from silver white to blue. It's not a cab really, just a pre-polished sliver of stone, done as a test.

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 Post subject: Re: Springsure labradorite
PostPosted: Thu Jul 14, 2016 1:17 pm 
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Cool effect, Lefty. Looks like adularescence maybe?

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 Post subject: Re: Springsure labradorite
PostPosted: Thu Jul 14, 2016 3:40 pm 
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ephsea wrote:
Cool effect, Lefty. Looks like adularescence maybe?


Yeah, it has to be ephsea. It's a little patchy in this tiny piece and when you look through the side you can see little platelets floating at different levels (though always parallel to one another). I polished a few other pieces that seemed to have a little bit in them, one shows a rainbow effect. They're all just bits of rubbish though.

We're having an unseasonally wet winter here, it's usually mild and dry. Heavy rain is forecast across Central Queensland over the next few days, that might bring some more of the stuff to the surface out there.


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 Post subject: Re: Springsure labradorite
PostPosted: Sat Jan 14, 2017 10:41 am 
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Love the photos, thanks for sharing!

The feldspar group is hard to understand, plagued with old names and varietal names.

Currently, "labradorite" is not an accepted mineral species; it's now anorthite.

Ever find a hint of crystal faces on your Aussie anorthite, or one in matrix?

Sounds like a good place to work!


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 Post subject: Re: Springsure labradorite
PostPosted: Sat Jan 14, 2017 2:40 pm 
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Labradorite was never its own mineral, it's a name for a compositional range in the plagioclase spectrum. That level of specificity does matter for gem purposes and just using endmember names gives the wrong impression.

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 Post subject: Re: Springsure labradorite
PostPosted: Sat Jan 14, 2017 7:25 pm 
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Icehut wrote:
Love the photos, thanks for sharing!

The feldspar group is hard to understand, plagued with old names and varietal names.

Currently, "labradorite" is not an accepted mineral species; it's now anorthite.

Ever find a hint of crystal faces on your Aussie anorthite, or one in matrix?

Sounds like a good place to work!


Cheers Icehut.

The "labradorite" from this locality does not seem to have been exposed to much weathering and typically comes in blocky, rectangular pieces, often with some perfectly flat faces - I can't recall the proper name of the crystal structure. Very few pieces that I have found show any rounded weathering. My father once bought a small bag of the material from a local gem show for a few bucks and all of the stones were very smooth and rounded - I'm suspecting that the guy may have tumbled them to achieve the weathered look that people typically expect from gem rough.

I have found bits of basaltic rock with pieces of the feldspar embedded in it, I'll see if I can find where I put them and take a photo.

I was polishing it with CeO until recently - I've found that 100k diamond on a Matrix does a good job without any of the scratching problems it can be prone to. It's probably being composed of multiple layers that makes it a bit prone to that. Mind you, CeO still does a good job but it can often take a bit longer to keep polishing out the scratches that tend to appear. I made the guess that diamond might overcome said problems since it tends to cut away hard and soft things at about the same rate, lessening any undercutting tendencies. Seems to have worked anyhow.


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 Post subject: Re: Springsure labradorite
PostPosted: Mon Jan 16, 2017 3:40 pm 
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Shattered piece embedded in host rock....

Image

Image

Tiny bits embedded in vesicular basalt.....

Image

And an unexpected find - a tiny thunderegg, about the size of a marble. I was expecting everything except the core to be soft and crumbly but it isn't. In fact, it's quite hard, like a sort of porcelain agate. It's the only such piece of material I've found at the site. I've also found a few bits of something resembling potch.

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 Post subject: Re: Springsure labradorite
PostPosted: Mon Jan 16, 2017 4:16 pm 
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That's a classic nodular agate right there. Thunder eggs occur in rhyolites. Round agates like this are classic basalt territory.
I'm not sure how the extra big plag crystals form in basalt (or end up in basalt anyway) but they do tend to have etched crystal faces.

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 Post subject: Re: Springsure labradorite
PostPosted: Mon Jan 16, 2017 6:47 pm 
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Aha! I called it a thunderegg because it looks like one of the thundereggs from Mount Hay - which I now know to be the remains of a rhyolite volcano.

Not overly colourful but it does resemble some of the stuff from Agate creek that the people from the gem club I met when visiting the in-laws in Atherton last week referred to as "porcelain agate".

Yes, the Mount Hay eggs have a core (often star-shaped) of agate and/or crystals and an outer shell which is very much softer. So I was a bit surprised at how hard the outer layers were when I put it against the little flat lap on the cabbing machine. At first I just assumed that the lap was nearly worn out (it almost is) but when I tried it on another, the whole nodule seems quite hard, rather than just the centre. It'd be nice to think that there might possibly be a deposit of good agate around there somewhere.

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I'm not sure how the extra big plag crystals form in basalt (or end up in basalt anyway) but they do tend to have etched crystal faces.


Yeah, it's strange that nearly everything I've ever found there - a few pounds of stones I guess by now - is angular with flat faces. The number of smoother ones with a stream-worn appearance I've found I could probably count on one hand.

But a small creek runs through the deposit, perhaps the seller got them from a spot further downstream, after they had been subject to wear?


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 Post subject: Re: Springsure labradorite
PostPosted: Sat Jan 21, 2017 12:05 am 
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Lefty wrote:
Image

So I see the rumors of rainbow moonstone in Australia were true! Would be neat if you managed to track down a deposit of similar quality to that of Tanzania's stuff. :)


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 Post subject: Re: Springsure labradorite
PostPosted: Sat Jan 21, 2017 4:28 pm 
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Shifter55 wrote:
Lefty wrote:
Image

So I see the rumors of rainbow moonstone in Australia were true! Would be neat if you managed to track down a deposit of similar quality to that of Tanzania's stuff. :)


That would be nice!! :D

There's apparently some quite nice stuff at Moonstone hill, west of Charters Towers - some of it apparently shows an orange shiller.

The nearby peridot diggings at Chudleigh Park have been closed down - someone tripped over and hurt themselves and decided it was the landholders fault and sued, so another good area has been lost :( The people at the lapidary club at Atherton told me something similar happened at Mount Gibson where I dig topaz when I go up to visit the in-laws (it was too wet this time). You can still go in but only under strict conditions.

Same with the garnet dig at Proston - ruined by public liability. The Australian penchant for suing someone else just because they didn't watch where they were putting their clumsy feet while out in the bush is just wrecking fossicking areas everywhere. Genuine, committed fossicking fanatics would be unlikely to destroy their own hobby by engaging in such behaviour - it's the idiots who hear about something and go out for a look just for the hell of it, then leave rubbish lying around etc who do this sort of thing. They don't care that they're ruining it for the rest of us :x


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 Post subject: Re: Springsure labradorite
PostPosted: Sat Jan 21, 2017 11:58 pm 
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Lefty wrote:
There's apparently some quite nice stuff at Moonstone hill, west of Charters Towers - some of it apparently shows an orange shiller.

The nearby peridot diggings at Chudleigh Park have been closed down...
Same with the garnet dig at Proston - ruined by public liability... ...They don't care that they're ruining it for the rest of us :x

I've been wondering about the stuff from Moonstone Hill, apparently some has a golden body colour so that + white schiller would produce an orange sheen, I've got some Indian peach moonstone with a similar effect. Unfortunately it's a lower priority than Prehnite and Harts range materials at the moment...

Do you think the Hunters and Shooters clubs have a similar problem with the public and liability?
I feel a lot of these sites should be a club-only thing as you get supervision and them taking the liability, as it is one thing to be a gemcutter, and another to be an experienced outdoorsman that respects the environment and understands that it isn't their private playground...


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 Post subject: Re: Springsure labradorite
PostPosted: Sun Jan 22, 2017 11:58 am 
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Lefty,

The predisposition to stupidity isn't confined to Australia... I have to deal with it on a daily basis.
I despise the lack of respect some people have.
I believe it's a tiny minority, but they ruin it for the rest of us.
It makes me angry when I go way back into the woods, far further than others, to find what I came for and then get back to the well traveled trails that someone has left a Starbucks cup and other garbage there because they were too lazy to carry it out.
Access to one site was lost because and idiot camped there for an entire summer, became belligerent to anyone that tried to dig there, and of course, left garbage everywhere.
There are places I get to go to and see only because I have the keys to the gates: They all got locked due to garbage dumping, and morons shooting everything up.
This year, one of my solar powered sites had bullet holes in the just installed panels.
At another one, the panels disappear on a regular basis, and the weather station is vandalized, in spite of the government flagging that this is a vital fire weather monitoring site.
I wish our society were much less litigious... We need common sense to prevail, for people to take responsibility for their own actions.
One of my friends has a saying: "Stupidity should be painful". It should be painful only for those that are stupid!


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 Post subject: Re: Springsure labradorite
PostPosted: Sun Jan 22, 2017 3:19 pm 
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Quote:
Do you think the Hunters and Shooters clubs have a similar problem with the public and liability?
I feel a lot of these sites should be a club-only thing as you get supervision and them taking the liability, as it is one thing to be a gemcutter, and another to be an experienced outdoorsman that respects the environment and understands that it isn't their private playground...



Not too sure shifter - shooters would be operating under pretty strict conditions I think, unlike a fossicking general permission area where anyone can just show up any time.

There's a lot of dedicated fossickers who aren't really club-type people - as Dan pointed out, a lot of miners would rather talk to a rock than a person - but I get what you're saying. A club is going to do all the right things. Unless it's a government designated fossicking area (I think Chudleigh Park and Proston were just private properties with general permission given) then the owner reserves the right to withdraw permission at any time. There quite possibly are some areas that only certain clubs have access to.

Quote:
The predisposition to stupidity isn't confined to Australia... I have to deal with it on a daily basis.
I despise the lack of respect some people have.
I believe it's a tiny minority, but they ruin it for the rest of us.
It makes me angry when I go way back into the woods, far further than others, to find what I came for and then get back to the well traveled trails that someone has left a Starbucks cup and other garbage there because they were too lazy to carry it out.
Access to one site was lost because and idiot camped there for an entire summer, became belligerent to anyone that tried to dig there, and of course, left garbage everywhere.
There are places I get to go to and see only because I have the keys to the gates: They all got locked due to garbage dumping, and morons shooting everything up.
This year, one of my solar powered sites had bullet holes in the just installed panels.
At another one, the panels disappear on a regular basis, and the weather station is vandalized, in spite of the government flagging that this is a vital fire weather monitoring site.
I wish our society were much less litigious... We need common sense to prevail, for people to take responsibility for their own actions.
One of my friends has a saying: "Stupidity should be painful". It should be painful only for those that are stupid!
Lefty,

The predisposition to stupidity isn't confined to Australia... I have to deal with it on a daily basis.
I despise the lack of respect some people have.
I believe it's a tiny minority, but they ruin it for the rest of us.
It makes me angry when I go way back into the woods, far further than others, to find what I came for and then get back to the well traveled trails that someone has left a Starbucks cup and other garbage there because they were too lazy to carry it out.
Access to one site was lost because and idiot camped there for an entire summer, became belligerent to anyone that tried to dig there, and of course, left garbage everywhere.
There are places I get to go to and see only because I have the keys to the gates: They all got locked due to garbage dumping, and morons shooting everything up.
This year, one of my solar powered sites had bullet holes in the just installed panels.
At another one, the panels disappear on a regular basis, and the weather station is vandalized, in spite of the government flagging that this is a vital fire weather monitoring site.
I wish our society were much less litigious... We need common sense to prevail, for people to take responsibility for their own actions.
One of my friends has a saying: "Stupidity should be painful". It should be painful only for those that are stupid!


Yes, it really sticks in your throat doesn't it? There's an old amethyst dig site not far down the road from where I live and myself and some other regulars I would often meet there would go around each time before starting digging, gathering up the rubbish that had simply been dumped on the ground. How hard is it to just take your rubbish away with you?

There probably always was a problem with rubbish and vandalism but the litigation thing is an issue of more recent years. Everything is somebody else's fault it seems. The owner of one of the major lapidary suppliers here (Leah Lane of Aussie Sapphire) told me that they once considered setting up a tourist park on their old sapphire lease after they had ceased mining since there was still enough stone in the ground for such a venture to be viable. The advice they received was - don't even think about it. It isn't worth the risk of getting sued.

On the last trip to Mount Gibson, my father had a bad fall. He slipped over in some loose dirt and rock on the steep slope and went bouncing down the mountain side, going over a small cliff and landing among a bunch of granite boulders. He was very lucky not to have been seriously injured or even killed. But it was simply an accident - at no time did we ever consider that it was the fault of the property owner with whom the state government has an agreement to let it out as a fossicking area. But since that day about 9 months ago, it seems somebody else also had an accident there and decided the landholder was responsible for their mishap. I don't know what the outcome of the lawsuit was but it has understandably made the property owner very wary about allowing people in.


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