Questions tagged [minerals]
For questions about minerals, i.e. naturally occurring crystalline chemical compounds. Also consider [metallurgy].
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Does Light Behave the Same in Crystal-Field Splitting, PPL Pleochroism, and XPL Interference Color?
My understanding in electromagnetic radiation is pretty weak; I learned of crystal-field splitting, where d-orbitals cause photons in visible light, and now we are covering how light shows up in a ...
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Bragg's Law: Don't Waves have to Overlap to Interfere?
This might be an absurd question, but I just want to make sure I am understanding things right; I have not touched trigonometry in a two years and things are not adding up.
The common model to depict ...
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Rock tumbler - gas release and absorbtion
I have a rock tumbler - you take rubber barrel, put some water, silicon carbide grit and random rocks inside and spin it for weeks to make rocks shiny.
It always goes like this - for the first several ...
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Is mineral quartz resistant to sulfuric acid?
We intend to use mineral quartz as a filler in a composite grout.
"Quartz, known as silica or silicon dioxide, this mineral is allochromatic with a hardness of 7 on the Mohs scale, specific ...
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Pauling's Rule 1: How Did We Relate Cation/Anion Ratio to Coordination Number?
Pauling's rules are used to predict the crystal structure of ionic minerals. The first rule is as so:
Radius Ratio Principle: Cation-anion distances are equal to the sum of their effective ionic ...
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How do manganese nodules in the ocean sustain oxygen production without depleting over geological time scales?
The news reports that manganese nodules on the ocean floor produce oxygen through electrochemical reactions. But how do these nodules sustain themselves without depleting? Do they replenish their ...
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What is the highest known temperature where micelles exist?
What are the two liquid phases involved in the formation of roughly spherical micelles at highest possible temperatures? What about a surfactant? At how high temperatures have micelles been observed ...
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Salts solubility and speciation calculations using PHREEQC
I am collecting data from literature for CO2 solubility in aqueous solutions. These are usually synthetic brines and are reported as molalities or wt% of salts or salt mixtures (I have NaCl, KCl, ...
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What is the source of the intense blue colour of ultramarine pigment?
The pigment ultramarine was once a rare, expensive and highly prized pigment for artists because of its intense, long lasting blue colour. It was one of the most expensive pigments used in renaissance ...
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synthesis of Red Lead, Pb3O4
I have tried heating $\ce{PbCO3}$ at $\pu{400 ^\circ C}$ temperature to form $\ce{Pb3O4}$. After sometime of heating, only a layer of $\ce{Pb3O4}$ is made and the reaction does not complete. The ...
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Are there tenebrescent minerals like KCl, but ideally resettable with UV/IR?
Is there a ‘simple’ mineral that is tenebrescent (getting reversibly darker on irradiation), but is resettable with UV or IR?
Hackmanite, spodumene and tugtupite (Wikipedia examples for tenebrescence) ...
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Besides diamonds, are there any stones without oxygen in composition? [closed]
In my inpression, the most of stones are oxides and hydroxides, correct me if I am wrong.
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Why would iron found in a nanoparticle not technically be a mineral?
An quote from an article at https://newatlas.com/science/antarctica-blood-falls-iron-red-water/ states, "Now a new study has examined samples of the water and found that the iron appears in an ...
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What does the 'S' stand for in base-centered cubic crystals and Bravais lattices?
The 'I' used for body-centered systems is for the German word Innenzentriert and the 'F' for face-centered is for Flächenzentriert, also German but what about the 'S' for a, b, or c base-centered ...
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Can limescale actually "etch" glass? [closed]
There are lots of articles on the internet about limescale "etching" glass due to the porous nature of glass. However, as I understand it, limescale is just calcium carbonate so can it ...
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Database of atomic crystal structure data or images of rocks and minerals?
I am looking for crystal structure images so I can redraw them in a nice form. However, I don't seem to find much searching Google.
Perhaps this is a slightly better example (searching for Quartz ...
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Number of bridge oxygen atoms in a silicate mineral
Total number of oxygen atom(s) which act(s) as bridge between any two silicon atoms in a mineral with composition $\ce{MM’Si3O_x}$ $(\ce{M}$ is the divalent metal ion and $\ce{M’}$ is the tetravalent ...
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effect of solution contact angle with KCl and NaCl ore on dissolution rate
I am working on a potash solution mining project (NaCl solution injection) and it is said that in the mine cavern, the contact angle of the solution with cavern wall can have impact on the dissolution ...
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Experimental setup
I would like to know your opinion regarding the setup of a system for oxygen purging with nitrogen. Before ordering the necessary materials, I'd like to be sure if this setup is feasible or if it can ...
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How many bonds does oxygen really make in minerals?
I'm studying some metallurgy things and interested in iron oxides.
The simple 2-D representation of a mineral like hematite shows $\ce{O=Fe-O-Fe=O}$.
But the crystal structure seems to show each ...
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Why is the only natural source of radium compounds uranium minerals?
A common mineral of barium is barytes, or barium sulfate ($\ce{BaSO4}$). Because elements in the same periodic group have similar chemical properties, we might expect to and some radium sulfate ($\...
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Why does calcined feldspar crumble?
For context, I am a potter and am interested in collecting and processing all materials that I use by myself. One of the processes which I use is calcination of certain minerals like feldspar, so that ...
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What is calcined lawsonite?
For context, I am planning to try and use this sample to make a ceramic glaze.
I recently collected a sample of what I think is lawsonite, which has the chemical formula $\ce{CaAl_2Si_2O7(OH)_2*H_2O}$....
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Why are the rare Earth elements divided into light and heavy categories?
Rare Earth's up to z=62 (Samarium) are often called 'light' rare Earths, while z=63 (Europium) and beyond are sometimes referred to as 'heavy' ones. Why such distinction? I didn't have come across (or ...
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Is selenite (hydrous calcium sulfate) dangerous when you grind it up?
I was wondering about the safety of a specific mineral, Selenite. From my research, I have read that selenite is the crystalline form of gypsum, which is hydrous calcium sulfate. I was wondering if I ...
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Si(OH)4 vs. H4SiO4 vs. SiO2.2H2O
Can someone please explain to me what is the differences between $\ce{Si(OH)4}$, $\ce{H4SiO4}$, and $\ce{SiO2.2H2O}$? I am currently studying sandstone acidizing geochemical models and this question ...
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Extracting other mineral from salt in evaporated seawater
I recently stumbled upon this news:
Seawater contains 47 minerals and metals. Starting with the most abundant and proceeding to the least abundant, these are chloride, with a concentration of $\pu{18 ...
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How is Potassium present in Potato (form) and where does it come from originally? [closed]
I was going through the concept of Boiling to reduce the potassium in Potatoes, which means $\ce{potato + water +heat -> potassium + X}$. $\ce{X}$ is potato with reduced potassium. I am more ...
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How do I prevent oxygen interfering when I prepare a FeCl2 solution from anhydrous FeCl2 powder?
I have a bottle of anhydrous $\ce{FeCl2}$ powder (from here; it is 98% pure and was kept in a glovebox after opening it for the first time to minimize reactions with oxygen) and want to make this into ...
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What's the difference between Zinc Ascorbate and Zinc Gluconate?
I've been looking at a dental product for pets, called MAXI/GUARD Oral Cleansing Gel and it states it uses zinc ascorbate/taurine, however in the ingredients I found elsewhere it instead lists zinc ...
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What's the most effective way to reliably trigger and observe hard water scale buildup at a micro level?
We live in an area that's got some really hard water. It's so hard that it kills most of the fish we try to care for in our aquariums and shrimp?... forget it. While this is sad and challenging for ...
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Why are lead and zinc commonly found together?
Copper, silver, and gold are often found in combination. That makes sense to me, because they are members of the same chemical family. Likewise, I would expect nickel palladium, and platinum to be ...
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Commercial chalk for kids composition
I have no background in chemistry whatsoever. However, I'm very interested in sidewalk chalk composition. I read that chalk can be both either made out of gypsum or chalk (calcium carbonate). However, ...
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Is it true to say that as of 2020, chemists can create any gemstone, from 1 to 10 level of Mohs' Scale strengths, artificially? [closed]
Please, I have a question here as a non chemist:
Is it true to say that as of 2020, chemists can create any gemstone, from 1 to 10 level of Mohs' Scale strengths, artificially?
If so, please detail ...
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How much sodium hydroxide would it take to dissolve one tonne of bauxite? [closed]
Generally speaking what proportion of NaOH would be typically required to dissolve one tonne of crushed bauxite of average purity?
Also are varying quantities required for gibbsite, böhmite and ...
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When and how do mineral chelates separate in the body?
If one consumes an amino acid chelate such as iron bisglycinate, it is generally absorbed intact as far as I am aware. At some point, presumably the iron could be used for say hemoglobin synthesis and ...
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How can chemists distinguish pure chemical element specimens that look almost "the same" as well as what deposit is what in a multimineral mined rock?
As a non chemist I am most often charmed when visiting Wikipedia articles of chemical elements and see images of very pure specimens of element after element, proton by proton, and often also metal ...
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Some substances appear white when crushed while others do not. Why?
Calcite crystals are semi-transparent but turn white when crushed. I used to think that it has something to do with the scattering of all wavelengths of light from small particles. But that cannot be ...
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Chemical structure of Turquoise [closed]
I know nothing about chemistry, I managed not to take it in correspondence high school. I don’t know how to read or make sense of this: $\ce{CuAl6(PO4)4(OH)8.4H2O}$ the chemical formula of turquoise. ...
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How does a vitamin differ from a mineral [closed]
At the molecular level, I would like to know fundamentally how does a vitamin differs from a mineral. I understand both have, to say, Fe (Iron), then what exactly makes it a mineral Iron or a vitamin ...
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Reaction of getting jarosite from pyrite
I am doing a PhD about archaeometry in order to study the contaminations and alterations that occur to the ceramics which are buried in a marine environment.
In my research, I have found pyrite in the ...
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Remineralization of ro water [closed]
Hello we are trying to prepare a solvent based solution of different kinds of minerals which can be added to reverse osmosis permeate water so that some of the essential minerals can be added back to ...
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What gives rise to the color of sapphires?
Sapphires are composed primarily of $\ce{Al2O3}$ (in pure form colorless) as well as Fe and Ti (trace impurities responsible for the color). I know that the proportion and identity of trace elements ...
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Use of cryolite and fluorspar in electrolytic reduction of pure alumina by Hall-Héroult process
Cryolite $\ce{(Na3AlF6)}$ and fluorspar $\ce{(CaF2)}$ are added to alumina to lower the temperature of the mixture from $\pu{2000 °C}$ to about $\pu{900 °C}$ and also to increase the conductance.
But ...
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How is hair tissue mineral analysis performed?
This might be a mixed chemistry / physics question, but I've always wondered what methods were used to precisely determine the levels down to trace amounts of all minerals in human tissues. I know ...
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Is there pure iron in nature?
Is there pure iron in nature, would that be not become Iron Oxide (rust) immediately because of the humidity? How do we produce iron ore/dust on the lab/industry?
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How can I reduce sodium chloride levels in water, without removing other minerals?
How can I reduce sodium chloride levels in water, without removing other minerals?
Good day,
I make a sole from Himalayan Salt which I add to my Reverse Osmosis treated water to ensure my body isn't ...
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Chemical formula of fluoroapatite
My textbook says the formula for fluoroapatite is $\ce{CaF2 * 3Ca3(PO4)2}$, whereas according to Wikipedia it's $\ce{Ca5(PO4)3F}$.
What is the correct chemical formula of fluoroapatite and why there ...
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How can I clean stained garden rocks?
I have some white garden pebbles which are now yellow with trace of rust. I have tried to soak them in bleach diluted with water without success. Could I receive suggestions of an appropriate ...
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How are Uranium and such materials made
I was wondering, how are materials like uranium, plutonium and other radioctive materials made. Do they all come from the old exploded stars and just been in the mountains for millions of years. Is ...
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