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Post by Ric on Nov 10, 2008 16:20:33 GMT 10
A few years back I was shown some indicator rocks which the person who showed me called "Paint pot"
The rocks are hard type of rock with a very noticable red all through them, sometimes in quite bright bands. There are also some small intrusions of quartz in some.
Can someone tell me the proper name of this rock.
Cheers Ric.
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Post by bunyip on Nov 10, 2008 16:30:39 GMT 10
Do you have a photo Ric may help...Bunyip
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Post by Ric on Nov 10, 2008 16:36:45 GMT 10
I've got a couple of pieces. I'll try and either scan or photo them. Ric.
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Post by Ric on Nov 12, 2008 15:05:30 GMT 10
OK let me see if I can get this new fangled photobucket thing to work Anyone know what these rocks are? The top one has a very shiny graphite like appearance when looked at from certain angles and also has some deposits of a silvery metallic stuff in some cracks. The lower one has none of this. Hee Hee whacko It works
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budgie
Super Sluicer
Posts: 281
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Post by budgie on Nov 12, 2008 15:40:36 GMT 10
Ric, I am sure what you have there is red Jasper. Gemhunters and cutters love the stuff. Put the stones into water and you will see all the lovely colour and patterns that look brilliant when cut and polished. When I lived in Coober Pedy we used to throw tons of it on to the mullick heaps. All we were looking for was Opal. Years later, back in civilisation, I learned about Jasper and some other stones.
Cheers, Budgie
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budgie
Super Sluicer
Posts: 281
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Post by budgie on Nov 12, 2008 15:45:59 GMT 10
Oh! I have no idea what the metallic streak may be. I suppose it all depends on the area the Jasper was found. All we used to find besides Jasper was tons of Gypsum.
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Post by prospekta on Nov 12, 2008 15:53:54 GMT 10
If it is hard could be Jasper, if it is reasonable soft or crumbly when crushed more likely a type of Shale.Both good indicators for gold.
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Post by bunyip on Nov 12, 2008 18:35:26 GMT 10
I have a lot of photos here ric of the same jasper but the photo bucket thing is a Hassle and wont work for me..Bunyip
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Post by Ric on Nov 12, 2008 19:48:28 GMT 10
No worriesBunyip. I got your email OK. Thanks Thanks Budgie & Prospekta for your input too. Cheers Ric.
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budgie
Super Sluicer
Posts: 281
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Post by budgie on Nov 12, 2008 21:54:03 GMT 10
Bunyip, Are your pictures in Photobucket saved as "Jpeg" or as "gif" ? The "gif" won't work because it has a different colour count, so Peter explained to me. I have to change some of my pictures to be able to post them. Good thing I married a computer nerd. Helps when I get stuck.
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Post by geoffbbungy2 on Nov 13, 2008 8:29:51 GMT 10
Interesting post Joe - jaspers ain't just jaspers obviously.The red jasper is quite common around Oz. Regards. Geoff/bbungy2.
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Post by Ric on Nov 13, 2008 11:50:02 GMT 10
G'day Joe Thanks for that link. I used to have it but lost it in the course of puter upgrades. After looking at a few different pics I think I have come across some Coffee coloured rocks too which could be jasper as well. I wish nowadays that I had an interest in this sort of stuff when younger. Back then a Rock was just a Rock maybe sometimes nice colours but just a rock. Now I find myself looking at all the rocks I come across with a magnifying glass to see what and how they are made up. Imagining how the heat and pressure has made them what they are. I try to relate them to geological reports so I might know what sort of rocks or overburden to look for. DAMN it life is too short. Cheers Ric.
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Post by araluen on Nov 13, 2008 12:20:02 GMT 10
It looks jasper to me also. It largely depends on where it was found. In the WA goldfield jasper is often associated with banded iron formations which are themselves a very favourable location for large gold deposits. In the younger areas of the eastern states jasper is associated with volcanic hot spring deposits which are often associated with what are called epithermal gold deposits. Also jasper is an iron rich and brittle rock type which favours shattering when subjected to rock stresses. The irn in the rock may also help to cause hot fluids to change their chemical character and if those fluids carry gold it may deposit out in the brittle iron rich rock. The silvery streaks may be specular hematite - another good sign.
Araluen (a geologist until last week when the US share market crashed throught he floor)
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Post by Ric on Nov 13, 2008 14:33:07 GMT 10
Hi Araluen, The rock definatley has a brittle sound to it when tapped against each other. The rocks came from Tuena creek, which I believe the area is know for its tin deposits too. Looking now at the silver/grey metallic deposits it looks like some alluvial tin samples I've seen.
Ric.
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Post by araluen on Nov 14, 2008 12:52:08 GMT 10
G'Day Ric
If its from Tuena then it is probably related to the volcanic rocks in the area. There are a number of copper-lead-zinc mines there and one of the rocks associated with those deposits (volcanic exhalatives) is a jasper-like chert. There would also be nearby quartz rich (or acid) volcanics. Gold is generally not associated with those rocks as the base metal deposits formed earlier than the gold deposits. While not having seen it I would say that tin would not be associated with that sort of rock from that area in general. Tin in the area is generally in a Greisen - a mica rich, suggary textures derivatie of late stage granite intrusives which were later than both the base metals and the gold deposits.
Araluen
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