Questions tagged [minerals]
The minerals tag has no usage guidance.
102
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Cobalt production in the Democratic Republic of the Congo (DRC): What percentage of the 70% production comes from illegal mines?
In Africa, particularly in the Democratic Republic of the Congo (DRC), approximately 70% of the world's cobalt is produced. However, I'm curious about the percentage of this 70% that comes from ...
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Is there any iron ore in New Guinea?
Generally speaking, iron is considered to be a very common resource. But I cannot find any evidence that there is any of it at all in New Guinea. Copper and gold, yes. Even nickel and cobalt. Iron on ...
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What explains the angled stripes of mineral visible on the side of some islands?
I was exploring some islands by boat recently and I came upon some pretty impressive rock formation. I'm interested in finding what mechanism produces those angle mineral strips. Some of them were a ...
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Why is there gold in the earth's crust?
I would naively assume that when the earth was formed and still molten, all the heavy stuff such as gold would have sunk to the centre, so almost nothing would remain in the earth's crust where humans ...
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Help with petrographic analysis of a complex mineral
While performing petrographic analysis in a rock composed mainly of plagioclase, pyroxene and olivine, I came across the mineral shown in the photo. Do you have any clues of what it could be?
The ...
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Where are all the minerals that have been mined?
I wondered, in general, what has happened to all the minerals that have been mined by humans. Do they still circulate in the economy and could be recovered through 'urban mining'. Or will they have ...
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Why does asbestos grow in a hierarchy of separable fibers of separable fibrils; why don't they stick to each other or grow into each other?
Wikipedia's Asbestos begins:
Asbestos (/æsˈbɛstɒs, æz-, -təs/) is a naturally occurring fibrous silicate mineral. There are six types, all of which are composed of long and thin fibrous crystals, ...
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How do housing developments affect the soil of the surroundings? Are the minerals/molecules in cement available to plants? Or is the soil too basic?
Calcium carbonate in cement can make the soil more alkaline but does that make large housing developments have a significant or negligible affect on availability of nutrients? Does it cause nutrients ...
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How does a sepiolite deposit form?
I'm interested in a material known as sepiolite. Wikipedia has the articles sepiolite in English and Sepiolita. in Spanish.
I'm more a person who tends to be more mathematical. But I'm interested in ...
2
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On QAPF (Steckeisen) diagrams, should Albite be considered on the Alkali feldspar or Plagioclase side? Or in-between?
QAPF diagrams are double ternary diagrams used for magmatic rock classification based on mineralogy.
Quartz and Feldspathoids are opposed on the pointy ends of the diamond, with Alkali feldspar and ...
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Is it safe to keep volcanic sulfur at home?
Took some sulfur stones while hiking on a volcano. Keeping them at home as a piece of decore. Is it safe to store it on a shelf? Can it ignite or somehow do harm to me or to my pets?
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Where is basalt in the Goldich dissolution series?
In relation to this experiment: https://www.remineralize.org/rem_publications/action-of-microorganisms-in-basalt-powder/
It is said that applying basalt rock dust to soil can improve soil fertility ...
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49
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Airborne geophysical survey in steep and undulating terrain. What is more important, energy conservation or orienting lines wrt to geology and why?
I am trying to design a cost and energy efficient aerial survey and have come up against the question, 'do we have to fly straight lines perpenducular to geology?' as not doing so could make for a ...
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How should we deal with geochemical anomalies in stream sediment?
We know that geochemical anomalies in stream sediment usually distributed along the drainage. Therefore, when we use stream sediment as the sampling medium and found an anomaly, we should trace the ...
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What is the "healthiest" rock?
When talking about rocks, i.e. an aggregate of minerals, which type would be the "healthiest"
I'm not talking about some voodoo crystal-healing stuff here, just if there is any rock ...
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287
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What are the compressive strengths of goethite and magnetite?
I am attempting to determine what the compressive strengths are of the minerals goethite and magnetite.
None of the research I did has proven to be fruitful. What I have found:
multiple studies ...
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Is there any mineral that survives hard degree metamorphism?
When a protolith enters in metamorphism, the minerals transform in other new stable minerals while the pressure and/or temperature increase.
Is there any mineral that would not be affected by a high ...
user20559
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How to genetically classify a weathering mineral or a mineral formed in soil?
Coming from this question and the answer, a proposed genetic classification of minerals:
Endogenic: Magmatic, Metamorphic, Hydrothermal.
Exogenic: Supergene, Sedimentary.
My question is how would ...
user20559
3
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1
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74
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What questions to ask to students from a mineral guide dataset?
I am programming an app that consist in 180 mineral sheets of interest for geology students.
My database have the following fileds:
Identifier
Name
Name 2
Type
Class
Formula
System
Environment1
...
user20559
4
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59
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Why is Melanterite white or colorless?
I've read that melanterite (FeSO4*7H2O) is colorless or white and gets to be green to blue with increase in Cu2+ impurities. But from my chemistry experience I know that iron sulfate is green when in ...
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44
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"Down wash" as a source for mineral particles in the soil
In a previous IGCSE examination paper$^1$, the following question was asked and answer provided:
State one source of mineral particles in soil.
Marking Scheme:
Accept any one of:
rock;
down wash;
...
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42
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Can geochemical anomalies of stream sediment samples be used directly for mapping targets?
We know that geochemical dispersion in stream sediment is much widespread, facilitating discovering mineral targets in a regional scale. However, we also know that there should be discrepancy in space ...
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Are there minerals that can't scratch each other but have different hardness on Mohs scale?
So I was reading here that Mohs scale is not transitive and therefore could not overcome the comparative phase in order to be turned into a measurement procedure.
As it is written in the webpage, &...
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550
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Avoiding fake trinitite
I would like to get some trinitite for my rock and mineral collection. The problem is that there is apparently a lot of fake trinitite for sale in the internet.
How do I avoid the fakes, and be sure I ...
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125
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Term for the Process of the Early Earth's Crust's Changing Mineral Composition
In the book, Story of Earth-The First 4.5 Billion Years, From Stardust to Living Planet, by Robert Hazen, Chapter 3: He discusses the changing mineral composition of the early Earth's crust from ...
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153
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How to identify chemical property and structure of rocks?
I am interested in identifying the properties of rocks. For example, black opal is shiny and can emit 5 different colors based on different lighting conditions. Is there a way for an amateur to be ...
2
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0
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40
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Ore prospecting and the low-hanging fruit effect
I'm trying to acquire an understanding of how the difficulty of prospecting for useful ore has increased over historical timescales.
Intuitively, I would expect that centuries or millennia ago, you ...
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60
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Ore Deposit Identification
What type of ore deposit does this rock best represent?
A rock with a porphyritic texture is cross cut by a stockwork of
quartz veins. Bordering the veins is extensive alteration of the host
rock. ...
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701
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Cleavage of minerals
What is the difference between 3-dimensional cleavage and cubic cleavage?
I think, they are the same, but I am not sure about if I was right or not.
4
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166
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How can the 'crystal cleavage' of apatite have a four-digit number?
On Wikipedia's page for apatite, the crystal cleavage is listed as [0001] or [0101], which I assume are Miller indices....
But how can there be four numbers/digits instead of two, like there usually ...
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280
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How is it possible for rocks to be trapped within another type of rock?
More specifically, I would like to know how the rocks in these pictures have formed:
If this is because magma has melted and trapped the other rocks inside, do they have a different melting point ...
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What causes dye to bleed from an agate stone?
I came across this review on Amazon. The cold drink was placed on top of the agate stone and the dye bled and left a permanent mark on the table.
Why does this happen? Is it because of the ...
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257
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Are there any sulphides, sulphates, carbonates that cannot be dissolved by aqua regia?
I was looking into these specific minerals: arsenopyrite, pyrite, chalcopyrite, barite, calcite, dolomite. I investigate issues with tellurides not showing expected gold concentrations.
There is gold ...
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Looking for videos/GIFs of petrification/permineralization
Do you know of any good animations, videos, or GIFs of petrification/permineralization? For some students verbal and written explanations don’t work, they don't always visualize well. So it’d be ...
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Have fossils ever been found in the asphalt lakes of Trinidad and Venezuela?
La Brea tar pits in California are the result of ancient oil seepages and famous for the fossils of extinct animals which were trapped in the tar. The asphalt lakes in Trinidad and Venezuela are also ...
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How to genetically classify a mineral resulted from weathering?
I am writing a mineral guide for smartphones which classifies minerals according to their formation environment.
From sugestions on this related question, I changed the classification to:
...
user18590
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History of the Arctic Ocean
Much of the Arctic Ocean is fairly shallow compared to other oceans. There must have been times in the past during severe ice ages that a lot of what is now the ocean bed was above sea level. When was ...
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Can I just walk around Greenland with a UV light and find rare Earth minerals on the ground?
The NPR.org news article and podcast Greenland Is Not For Sale. But It Has The Rare Earth Minerals America Wants is interesting, and it includes a few large GIFs (too large to post here) that appear ...
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Database of mineral with images for a neural network application
I'm diving into data science and I'm looking for a complete database of minerals. I downloaded the csv file from http://rruff.info/ima/ . It contains 5516 lines of data but it does not have images or ...
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Hyperspectral Detection of Ore
How can I use hyperspectral satellite imagery to remotely detect copper or any prespecified mineral deposit in general?
Where can I find a database of the absorption and reflection bands of various ...
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2
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247
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Is this classification of mineral formation environments correct?
I am writing an app for students that consist in 180 sheets of the most common minerals on Earth's Crust.
One of the fields of the sheets is environment of formation.
It is important to me to ...
user12525
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Chloride ions for the salty seawater
Where does the chloride ions that are required for the salty taste of sea water come from ?
I know that it is the weathering caused by the slightly acidic (due to dissolution of CO2 with water) rain ...
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What's the difference between cleavage and fracture?
I see both terms refereing to fractures on crystals or minerals, so I wonder if they could be considered synonymous.
If no, what's the difference between both terms?
user12525
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Why do allophane soils behave as gels?
It is notoriously difficult to determine the texture of soil containing allophane and immogolite. According to the literature this is because the clay fraction "behaves as a gel", i.e. it's not ...
2
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1
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An oblique-square-prism crystal?
Does any mineral crystallize in the shape of an oblique square prism? If so, what crystal system (monoclinic, cubic, hexagonal, etc.) would such a mineral fall under?
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How are minerals classified?
What exactly is done to classify minerals in Earth Sciences such as Geology? How can it be known if one mineral is the same as another if they should be visually different?
user15196
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544
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How salty can snow/sleet be?
Can enough salt particulates be in the air to create salty snow or ice that is undrinkable?
Will ice form in sub zero temperatures through condensation in salty air?
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264
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What is cluster situation with respect to sand mining?
Guideline on handling cluster issues : The original Environmental Impact Assessment ( EIA ) notification does not provide for the procedure to handle cluster situation, which has been proposed in ...
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Preservation of clay items
I have a general question which may sound naive: archeologists eg in Ancient Greece take a lot of information from preserved pottery they found. What physical attributes of ceramic items made of clay ...
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165
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Where to start searching to find more radioactive minerals?
I'm pretty new to all this...
I've recently purchased a Geiger counter, and am hoping to locate rocks like pitchblende and other radioactive minerals for my collection.
I'm based in the North West ...
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