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Agates from Argentina. SOUTHWEST REGION : Ghost agate
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Author:  condoragatemines [ Sun Mar 03, 2019 10:00 pm ]
Post subject:  Agates from Argentina. SOUTHWEST REGION : Ghost agate

Ghost agate

Ghost agate deposit is located 20 Kilometers north of Petrified Forest National Park in Santa Cruz Province, Argentina.
This agate is found loose on the ground or semi buried under decompose Andesite.
The nodules are round or almond shape with very distinctive fortification pattern in white color suspended in clear chalcedony.
Some special features inside this agate are moss, plume, tubes, and curtains pattern.
The agate age is Jurassic, (160 million years old)
Small percentage of nodules are fluorescent green color under UV light short wave.

Attachments:
File comment: Same specimen of Ghost agate as the previous one under UV light short wave.
IMG_2938.JPG
IMG_2938.JPG [ 2.21 MiB | Viewed 5062 times ]
File comment: Ghost agate cut and polish
IMG_2933.JPG
IMG_2933.JPG [ 2.68 MiB | Viewed 5062 times ]
File comment: Ghost agate cut and polish
IMG_2965.JPG
IMG_2965.JPG [ 2.94 MiB | Viewed 5062 times ]
File comment: Ghost agate cut and polish
IMG_2913.JPG
IMG_2913.JPG [ 2.63 MiB | Viewed 5062 times ]

Author:  Barbra Voltaire, FGG [ Sun Mar 03, 2019 10:17 pm ]
Post subject:  Re: Agates from Argentina. SOUTHWEST REGION : Ghost agate

Is this another example of uranium contamination?
What is the source of the uranium?

Author:  condoragatemines [ Sat Mar 16, 2019 2:19 pm ]
Post subject:  Re: Agates from Argentina. SOUTHWEST REGION : Ghost agate

The green fluorescence color in this material is different than the other fluorescent green color agates that had been in contact with uranium salt.
I'm not aware of Uranium deposit near this ghost agates.
I don't think the fluorescence in ghost agate is due to contact with uranium salt.
What cause the fluorescence in ghost agate is unknown yet.

Author:  Stephen Challener [ Sat Mar 16, 2019 2:33 pm ]
Post subject:  Re: Agates from Argentina. SOUTHWEST REGION : Ghost agate

With that color I think uranium is inevitable, and it doesn't take much. Uranium is highly mobile in the hydrothermal fluids that agates form from so it's pretty easy for it to get in, and the source itself might be distant or long since eroded.

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