Questions tagged [mineralogy]
Questions relating to the scientific study and identification of minerals.
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How do cations control the crystal structure of silicate minerals?
Beyond the obvious fact that in many of the silicate subtypes they play an ionic 'glue' like role by bonding the tetrahedra units together; how do cations control the structure of a silicate and how ...
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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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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
...
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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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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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"Obicular" structures in basalts
I found spherical or globular structures, structures in basalts of a greenstone belt which underwent alteration and deformation. However, in thin section, these structures have undeformed pyroxene and ...
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Iron-nickel phase in pallasite meteorites
I have recently been learning and researching about meteorite types and classification. Pallasites are mainly composed of a 'solid-solution' of olivine crystals and an iron-nickel alloy. My question ...
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Saturation Index clarification
I have a problem with my project and I was hoping I would find some clarification.
I did some modeling with phreeqc to calculate saturation indices and found that calcite was saturated in an ...
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Formation of dolomite
What are the kinetic barriers to dolomite precipitation? Does it precipitate out in solution as quickly as Calcite does?
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What processes cause basalt to form a columnar structure? [duplicate]
I have run across many pictures of rocks that look like almost perfectly carved columns. For example: the Twyfelfontein Organ Pipes, the Basaltic Prisms of Santa Maria Regla, and the waterfall ...
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Why does Australia have no chrome?
I've been trying to collect resource data about Australia for a few years. Some good reference sites are AustraliaMinerals.gov.au and AustralianMinesAtlas.gov.au
Australia seems to be pretty rich in ...
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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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Melting point of minerals
Looking at this website, I can see the melting point of the following minerals: http://hyperphysics.phy-astr.gsu.edu/hbase/Geophys/meltrock.html
Apparently at a temperature of 1200 °C, all the ...
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Is it possible to determine where gold might be found based on a map, and if so, how? [duplicate]
Is it possible to locate potential gold deposits using maps that describe dominant rock type, altitude, vegetation, or geological formations?
(I realize that the location would probably still have to ...
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How does metamorphism change talc into soapstone?
My understanding is that soapstone is talc (hydrated magnesium silicate) which has been metamorphically transformed. However, it is not clear to me how this transformation affects the talc.
What is ...
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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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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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Where/how people find minerals
Forever I have seen little shops here and there offer minerals like those crystals and neat shaped rocks of different kinds, turquoise and amethyst and many others and such. But I never really thought ...
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Geological maps of British Columbia
I’ve been doing research into mineral deposits in B.C. I’ve been overlaying old claims maps onto Google Earth maps. Are there any good public maps for metallic minerals for British Columbia online?
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How can a crystal habit be round?
I am confused how hematite can have a "botryoidal" habit when its crystal structure is trigonal, which is an angled structure.
How can an angled crystal present itself as rounded?
If a botryoidal ...
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Is there any mineral identification techniques that works for all minerals?
Are there any mineral identification techniques that work for all minerals(non-metallic/metallic), so that an electronic device could be made to distinguish between all minerals?
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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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Name of majorite endmember $\ce{Mg3(FeSi)Si3O12}$
Does the majorite garnet $\ce{Mg3(FeSi)Si3O12}$ have a name?
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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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Ions & elements, which is the correct terminology to use when discussing chemical compounds in Earth Science?
Different textbooks use different terminologies when discussing the same chemical compounds, for example when discussing the minerals...
Elements / Compounds
Sulfide minerals consist of metallic ...
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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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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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Ore Deposit Determination
How are ore body sizes determined? What are the most reliable techniques of determining the size of ore deposits as well as their content?
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What are these features in the Tombouctou Region?
I’ve recently been very interested in globe-trotting via Google Earth. At first I was using it to plan out hikes to possible mineral deposits locally, or potential fossils/ archeology sites. However I ...
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Did we find cinnabarit?
We searched for cinnabarit in an abandoned mine (Google Maps, in Békásmegyer, Hungary). We collected these samples, but as we are not geologists, we are not sure what we found. Pictures about the ...
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Voronoi-like pattern in metal samples
What is this pattern in the samples' surface called and how/why is it formed? I remember having seen a similar pattern in galvanized sheets.
Photos of metal samples from Wikimedia Commons (here and ...
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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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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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Inorganic Limestone and Inorganic Gypsum
I read that limestone is made from the compaction of marine animals' bones. But, I am unable to find out why limestone could not have been produced from calcium occurring naturally (5th most abundant ...
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Gypsum saturation index
I did some geochemical modelling and found groundwater samples I have are saturated with respect to the mineral gypsum. I need some help with interpretation, more information is given below.
The ...
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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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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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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 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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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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Ore Reserve Definition
I've seen many papers on mineral deposits say something along the line of "a 100,000 tonne deposit of Zn, 1% grade." Does this mean there is 1% of 100,000 tonnes which is 1000 tonnes pure zinc, or ...
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Can crystal lattices be analogue? [closed]
This question might turn out to be more about physics then geology so apologies in advance if that is the case.
Years ago I read something that said in crystals "atoms have finite positions along the ...
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Connection between microbes and serpentinite?
Serpentinite belongs to the serpentine group. This group of minerals are metamorphic minerals caused a special process called serpentinization.
Serpentinization created serpentinite on the Earth's ...
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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?
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What is this Lake Michigan rock? [closed]
Rock found along northern Lake Michigan, (Charlevoix, MI). Made up of very thin crystalline layers. There are small, round bubble like bumps that protrude from the surface. Doesn't show well in the ...
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What disciplines of science are used in the locating and extraction of mineral resources? [closed]
Im trying to do an assessment but I just can answer this question!
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What does the unit cell of petitjeanite look like?
The question in Chemistry SE What is the crystal structure of bismuth oxyhydroxyphosphate (BOHP)? is about a catalyst synthesized by accident. A link in this comment points to the page https://www....
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Limitations on mineral precipitation from solution
If the solubility constant for a mineral is exceeded and, thermodynamically, a mineral is favored to precipitate in solution, are there any factors that may limit this from happening? Perhaps kinetics?...