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 Post subject: Re: Garnets
PostPosted: Thu Mar 17, 2016 3:17 pm 
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Location: Central Queensland, Australia
On the topic of garnets, I'm a bit surprised to hear that your Proston garnets broke up after faceting. I've had some for years and they're still going strong. Perhaps yours had hairline cracks in them that were hard to see against the dark blood-red stone. They aren't like sapphires. Some of them seem to begin life as a mass of crystal that breaks up into individual stones as it weathers.

I have a dark one on the dop now. I haven't cut the crown yet but it's looking positive so far about a design to get more light inside it. It's an extremely simple baguette-type, with the shallow pavilion consisting of only four big facets at 38 degrees to act as reflectors. I don't want to count my chickens before they're hatched but the long, keeled pavilion seems to be admitting a lot of light in through the side and reflecting it upwards, it throws a nice bright red flash in normal lighting without back lighting. I think one of the factors working might be the very long rectangular shape - not sure how it would go as a square, even with the shallow pavilion and crown. Anyway, cross fingers.


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 Post subject: Re: Garnets
PostPosted: Fri Mar 25, 2016 6:25 am 
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Hi Lefty, I just had a chance to read all the posts you did on your finds.
If you have, indeed, found a sapphire, it is a normal blue, green/yellow cross, basaltic Queensland sapphire.
My understanding is that you will not get a reversed C, A-B axis.
Have you cut it yet?


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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 6:05 am 
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Yeah, she's an interesting one Barry. I haven't cut it yet, there's a crack in the middle but I can't see how deep because there's a bit of rubbish around the edge blocking the view from that direction. I think if I invert it the crack should go with the normal amount of material that would be removed in cutting. But I think I'll strip back the bit of rubbish on the side for a better view first.

The most interesting this is how it seems to be the reverse of normal - green/yellow on blue rather than blue on green. Just like you note, it would be most unusual and I have never found one quite like it.

But this is a different location to the Anakie field. Hundreds of kms away in fact - completely different set of volcanoes.

Whatever it is, nothing I have tried will scratch it and it will scratch a rough sapphire. It really does look as though the green-yellow is the c-axis and the deep blue the opposing axis. Most intruiging.


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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 7:23 am 
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Hi Lefty, all our Aussi sapphires are Basaltic, regardless of where you find them. The magma hotspot that the continental plate slid over, is responsible for all our amazing geology, including all the volcanoes. They are scattered all over the place, and the high iron content in the Basalt gives us the blues we find.
Metamorphic sapphires are completely different, and are found in Kashmir, Burma, Sri Lanka, Madagascar, and Tanzania.
Getting back to your stone, it has the same source magma, even if it is 100's Km away from the big fields. The volcanic activity that spawned all these gems must have been stupendous, and the source vents can be anywhere within many, many Kms. The Lave plains fields are a good example, maybe 600km north.
I have just sought clarification on the Axis's, to see if they can be reversed. I will report what I find.
Does your sapphire show 6 sided crystal form on the green/yellow axis?
Or does it show growth lines in the structure to confirm your supposition?
We need more photos please.


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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 7:29 am 
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Yep, answer just came back from gemologist, you have a normal, blue, with green/yellow cross sapphire. Congratulations on the find, may there be many more.
Forget the garnets, chase the wily sapphire my friend.


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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 7:53 am 
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Hi Lefty
the c-axis(table) in Sapphires
the c-axis also called the optic axis(table for Australians :) ) will only show one color if you look straight down on it(no pleochroism), exeption is a pharaos eye in Australian stones its not pleochroism but will still show you more than one color. In Australian stones generally the table is the most saturated/darkest color you can find turning the crystal, exception yellows can be very difficult to find the table.
As I see a dark shadow in your first picture to the left of the stone and i the second picture on the top of the stone it seems to indicate some Silk that is layered parallel to the table, meaning in both of those pictures we will much likely look at the cross table.

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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 11:36 am 
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Quick clarification on basaltic sapphires: they are found in basalts but they definitely did not crystallize in the basalts. They were formed in a subducting slab, which often contain Al-rich sediments and are subjected to high temperatures but (geologically) low temperatures. The basalt just grabs them on its way up to the surface. That's why your sapphires are rounded--they are not at chemical equilibrium in the basalt and they start to dissolve.

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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 5:30 pm 
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Location: Central Queensland, Australia
I hadn't heard of green on blue nor even knew if it was possible, my thinking was based on the fact that different colours seem predominate in proximity to different volcanic vents, even on the same field.

I can't take a photo that shows what the eye sees since it is faint (and hopefully won't detract from the faceted stone), this drawing is about as good a demo as I can give. The green-yellow axis has features that we see when looking down the c-axis of a sapphire, namely the sergeant-striping that if continued right around would form a hexagon.

Image

The blue axis is difficult to see through but I've decided it isn't actually as dark as it looks, there's a band of dark, crappy corundum around the edge which hampers the light.

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Forget the garnets, chase the wily sapphire my friend


My thoughts exactly :D In this spot I'll have to find garnets in order to find the sapphires so I won't be throwing away any of the less-saturated garnets, they do cut a very attractive stone. But I'm just stoked to find sapphire so much closer to home, it's a long drive out to Reward!


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 Post subject: Re: Garnets
PostPosted: Sat Mar 26, 2016 5:36 pm 
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I'm actually not the first person to find sapphire in this region. Old records mention early gold prospectors finding green sapphires here and close by. But record of such things from colonial and early Federation days in QLD are usually sketchy at best. I had heard about this previously but dismissed it as mis-identification, assuming that they had found green garnets or epidote. Some of what they found probably were those things but they were also on the money with the existence of sapphires.


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 Post subject: Re: Garnets
PostPosted: Sun Mar 27, 2016 12:47 am 
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News of an odd find like that Lefty travels. From my experience in the gold fields in California, dig hard, dig fast, fill in your holes and cover your tracks. Your claim, your find, means nothing to the snipers that follow. I always made it a point, even in the circle of friends and family never to discuss true locations. Except one. My Orion claim, the legals from the original claim were written to follow the alignment of stars on the ridge top from a specific jump point in the month of February. Orions belt touched the ridge thats where it was. Took me 6 months to figure it out and I knew where it was.
Keep your legals if you have to for the find, but tell everyone else you found it near Perth, or Tasmania. Unless you dont mind giving what you worked for to those who didnt. Sometimes I miss prospecting, I really dont miss some of the wild west that goes with keeping a claim.
The green sapphires I pull out of Montana arent even close to that saturation.
Happy Easter!

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 Post subject: Re: Garnets
PostPosted: Sun Mar 27, 2016 5:48 am 
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Happy Easter to you to Dan! :)

Image

Closest I could find to an image of the Easter bunny with a basket full of gems.

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News of an odd find like that Lefty travels. From my experience in the gold fields in California, dig hard, dig fast, fill in your holes and cover your tracks. Your claim, your find, means nothing to the snipers that follow.


Yep, couldn't agree more. The exact location must remain secret. Given that it's private property, if people turned up unannounced it would probably be the property owner who would be the "sniper" - from 300 yards with a .30 cal :lol:


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 Post subject: Re: Garnets
PostPosted: Wed Apr 06, 2016 5:27 pm 
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Quote:
Yep, couldn't agree more. The exact location must remain secret. Given that it's private property, if people turned up unannounced it would probably be the property owner who would be the "sniper" - from 300 yards with a .30 cal :lol:


Lightweight! We use 50 cal. semi-autos around here, tripod mounted in the back of our pickups. With tracer rounds, so we can zero in on the elk :shock:


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 Post subject: Re: Garnets
PostPosted: Thu Apr 07, 2016 4:25 am 
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Orerockon wrote:
Quote:
Yep, couldn't agree more. The exact location must remain secret. Given that it's private property, if people turned up unannounced it would probably be the property owner who would be the "sniper" - from 300 yards with a .30 cal :lol:


Lightweight! We use 50 cal. semi-autos around here, tripod mounted in the back of our pickups. With tracer rounds, so we can zero in on the elk :shock:


I ate elk sausages ("smokies" I think they were called) when I was in Canada. With the kind of firepower you're talking about, you wouldn't need a meat grinder to make sausages, you must just scrape up the pulverised elk and pack it into sausage skins :)


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 Post subject: Re: Garnets
PostPosted: Thu Apr 07, 2016 5:34 pm 
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Lefty wrote:
Orerockon wrote:
Quote:
Yep, couldn't agree more. The exact location must remain secret. Given that it's private property, if people turned up unannounced it would probably be the property owner who would be the "sniper" - from 300 yards with a .30 cal :lol:


Lightweight! We use 50 cal. semi-autos around here, tripod mounted in the back of our pickups. With tracer rounds, so we can zero in on the elk :shock:


I ate elk sausages ("smokies" I think they were called) when I was in Canada. With the kind of firepower you're talking about, you wouldn't need a meat grinder to make sausages, you must just scrape up the pulverised elk and pack it into sausage skins :)


The guys I knew went for head shots. No trophy head, but a lot less messy :P


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 Post subject: Re: Garnets
PostPosted: Mon Apr 11, 2016 4:25 pm 
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At $2.20 per round they would need to shoot tracers because they can't afford to practice. Spray and pray it's the American way. [-o< I hope I hit something.

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