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Why is Geode sedimentary I always wondered why Geode is
sedimentary chemical. It has
very large crystals and it
looks like it has to be
igneous intrusive. Can you
explain to me in detail why
that is?
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Geodes form by precipitation of minerals from solution. That would make it a chemical sedimentary rock. They are not often found in intrusive igneous rocks because the geode needs a vug, or a cavity within the host rock in order to form. Intrusive igneous rocks rarely have vugs, but do sometimes have large fractures or joints that can be crystal lined similar to a geode. Geodes are more likely to be found in extrusive igneous rocks that have vugs formed by gas that comes out of solution as the rock cools rapidly (in comparison to intrusive igneous rocks). These vugs eventually may fill with fluid which carries dissolved calcite, quartz, and other minerals. As the fluid becomes oversaturated different minerals will drop out of solution forming layers of the geode and finally forming crystals within the center of the geode. The similar things that form in sedimentary rocks are often referred to as concretions, and these are seldom hollow. They may be composed of calcite, chert, or other minerals, and will often have concentric rings within them. However, they do not form within a vug or cavity, but instead appear to grow outward. Septarian concretions have crystalline filled fractures inside them that makes them quite attractive. Concretions appear in most cases to form from a nucleus and grow outward, unlike a geode's growth inward. |
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where can i find the AMD i am interested in the NX
model. i have looked all over.
newegg, nextag. is this thing
even available for a hobbyist
like me?
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http://cgi.ebay.com/AMD-Geode- NX-1750-K7-S462-S-462-CPU-PROC ESSOR-Pro-3000_W0QQitemZ320208 807751QQihZ011QQcategoryZ15919 QQssPageNameZWDVWQQrdZ1QQcmdZV iewItem http://cgi.ebay.com/RG049AA-HP -Compaq-t5725-Thin-Client-AMD- Geode-1500_W0QQitemZ1501995877 01QQihZ005QQcategoryZ11221QQss PageNameZWDVWQQrdZ1QQcmdZViewI tem |
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i want to sell my large the smokey crystal quartz is
roughly 12" by 12" by12" and
weighs about 35 kilos and the
geode is 18"long by 6"wideby6"
high and weighs around 15
kilos and the amethyst stones
are almost black
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A rock and mineral shop might. A university might as well, though geology departments tend to be poor. You can always try eBay or if you don't have eBay in Australia, I am sure there is some other online selling platform. Smoky quartz isn't worth too much and I'm not sure how much you could get for amethyst that isn't a nice, bright purple. |
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I have a geode, anyone know My dad found a HUGE geode. My
friend says its worth up to
$5,000. The problem is I
really need that money for
Braces, is there anywhere I
could sell it in Washington
State to get the most out of
it?
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Geode's are beautiful! I'm sorry that you cannot keep it, and need the money. But that's a reality of life. You could do some research on environmental websites, a website that specializes in Earth Science, rocks, volcanoes. Get more informed. Your friend isn't the best source, then with your information, you could look on Google for places that accept your Geode. You must make sure everything is legit, you don't want to be scammed! |
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I have a black rock with Have pic. Was found in ILL. in
farmers field.
How do i show pic?
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Could be countless options to your answer...perhaps a vesicular basalt with zeolites... |
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