Questions tagged [mineralogy]
Questions relating to the scientific study and identification of minerals.
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Why do mineral deposits exist in veins?
One would imagine that the various atoms of the periodic table would be well mixed in the earth's crust. Yet, certain locations on earth have large amounts of specific mineral deposits. Consider gold ...
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What kind of mineral rock is this? [closed]
Does anyone knows what kind of mineral is this?
I found it near a beach in Italy
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What determines the color of light emitted by thermoluminescent stones?
I recently stumbled on the concept of thermoluminescence, specifically when minerals or stones emit visible light after being heated. However, information about one aspect seems a bit unclear: the ...
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Simple explanation of what "preferential lattice expansion due to excessive magnesium adsorption", means
In the context of crystal growth, particularly saddle or baroque dolomite development, what does "preferential lattice expansion due to excessive magnesium adsorption" mean in practical ...
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What useful information could an ancient "mining compass" yield?
I read here and elsewhere that
Exploratory and reconnaissance surveys are frequently made with the aid of a magnetic compass [...] Early references to the application of the magnetic compass to ...
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Possibility of naturally cut diamonds
Is there a chance that diamonds may naturally occur as any of the geometric shapes in such a way that it is naturally brilliant and cut? Obviously, I am not expecting really sophisticated cuts but ...
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Monazite-(Ce): Non-integer ratios of substitutable elements
I've been looking at EDS data for monazite-(Ce):
And I noticed that (at the O=4 column) the ratios of substitutable elements are not integers. I thought that it was because of measurement errors, but ...
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How would I be able to store Hydrombobomkulite?
It dehydrates rapidly (hours) to mbobomkulite. So how would I be able to store it?
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What is a good definition for "lattice bound" and is iron within octahedral sites of illite considered lattice bound or interstitial?
The title pretty much says it all. I cannot find a satisfactory definition of "lattice bound", just a number of examples of it being used in literature. For example, in this paper about ...
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Does anyone know what the mineral of the year 2023 is?
I have been collecting every mineral of the year since 2012, and I have not found anything on last year's mineral.
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Why does Argentobaumhauerite have decimals in its chemical formula?
Argentobaumhauerite's Wikipedia page lists its chemical formula as $\require{mhchem}\ce{Ag_{1.5}Pb_{22}As_{33.5}S_{72}}$. Is there a reason this chemical formula is not represented as whole-number ...
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Good modern paper demonstrating differentiation of glauconite and berthierine using xrd or FTIR
I'm looking for a recent paper that demonstrates how one would unambiguously differentiate glauconite from berthierine and have yet to find something useful.
I'm running across a lot of papers seeming ...
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Estimation of rare earth elements in the SUAC complex
I am currently competing in a case study competition a part of which has asked us to estimate the amount of Nd, Pr, and Dy in the SUAC complex (Sung Valley Ultramafic-Alkaline-Carbonatite) in electric ...
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Is there a way to know what the concentrations of various minerals and ions in the water of a human usable hot spring are?
I have heard that there are hot springs in Greece which contain high amounts of ions and minerals (namely Lithium) that some people believe has beneficial impact on mental health.
I can't verify/know ...
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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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Is it possible that the rainbow sand dunes in Death Valley, California were formed by some massive mining in the ancient past? [closed]
I know there is a mainstream answer that thinks the rainbow sand dunes they be explained geologically... I just want to know if it's possible to form those colors and those dunes from mining? And if ...
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Hexagonal phenocrysts with a metallic luster?
I recently realized that I am surrounded by interesting rocks. Having no background in geology nor geologist friends, I rely on online resources to navigate the intriguing stuff I stumble across. But ...
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Could travertine buildup seal up cracks in limestone?
So after a recent freeze in Texas the following overhang collapsed. Presumably water in existent cracks froze and made the cracks even bigger as the water expanded. Combined that with an increase in ...
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What causes compositional banding in metamorphic rocks?
In the foliation of a gneiss for instance, minerals are segregated by composition.
What causes minerals phases to be grouped into layers like this?
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What stone/crystal is it? [closed]
I found this stone/crystal when I walked down the street few days ago.
I picked it up since it looks very different with other stones in the area,
I am really curious about what stone/crystal it is, ...
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List of thermodynamic properties of various minerals
Hi I am looking for a list or a database where I can find the basic thermodynamic data like the standard enthalpy or standard entropy! Do you know of one?
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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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Why is silver found mainly in lead
Apparently according to the Parkes Process silver is 3000 times more soluble in zinc than in lead. So why is it that most silver is obtained from galena?
Edit:
“ Silver mainly occurs as a contaminant ...
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What kind of chromium is in common limestone?
I was thinking of crushing up some common limestone for microminerals because the water where I live has nearly zero calcium content. So I read about the trace elements of limestone and It says ...
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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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Why is the Lunar crust anorthite?
The primordial Lunar crust is mostly calcic plagioclase. However, why did the Lunar Magma Ocean produce so much anorthite, why not a feldspar of a different composition, like albite or orthoclase for ...
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Difference between crystal and mineral
What is the exact difference between a crystal and a mineral?
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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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Looking for Rock/Mineral Identification Flowchart
As a christmas present, I bought a box of minerals/rocks for my girlfriend, who recently got interested in geology. Unfortunately, she could not attend the identification class in university. The box ...
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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 ...
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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
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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
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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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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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Isotopic dating of metamorphic rocks
I read in my physical geology textbook that sedimentary rocks cannot be dated using isotopic dating, because they are formed from fragments of other rocks and minerals, which if you were the subject ...
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Why were Fe-oxides not usually used for finding skarn Fe ore deposits in geochemical exploration?
I found that Fe-oxides were usually not used for vectoring Fe mineral deposits of skarn type in geochemical exploration. As an indicator element, the common practice told us Fe-oxides should be the ...
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Identifying metallic element or compound in murine clay
I have been doing a lot of digging in a thick murine clay as part of a construction project. In the course of doing this work, we noticed significant bands and streaks of blue color in the clay, which ...
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Artifical Ore Genesis?
From my understanding, the formation of ores can be reduced to a simple three-step process of the removal of minerals from a source via some mechanism, the transportation of these minerals, and ...
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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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What kind of rock is this? [closed]
A few years ago in Venezuela, parque nacional de Cainama, the tourist guide found and gave me this rocks, he told us that a geologist told him that those could be radioactive but no one believed him. ...
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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 ...
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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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Feldspar content of coarse-grained igneous rocks
From the chart, I would say that plagioclase feldspar is more abundant in coarse-grained igneous rocks than alkali feldspar, as it is found in all three listed, whereas alkali feldspar is only present ...
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Quartz mineral category
Different learning resources categorise quartz differently. Strictly speaking, is quartz a silicate mineral or an oxide mineral?
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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.
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Hydrocarbon resources extension. How?
Pardon my naive question. But I heard this argument quite sometimes.
One can find at the Schlumberger careers page the particularly interesting FAQ:
“We are often told that oil is running out. Why ...
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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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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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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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