Talk:Quartz

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Origin of "Quartz" in References[edit]

The reference to "Queensland University of Technology Origin of the word quartz" is broken in that there is a password requirement to get into QUT—consequently it is useless! Linmhall

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Tensile strength: 48.3 MPa

Pa = Pascals?


Pa = pascal(s)

S.


There is some controversy over density of quartz. Most references I've found say 2.65 g/cm3; see: [1] for details - Waveguy

Something is missing[edit]

I was looking over this article and found that the texture of Quartz is not included. I know that this is a small detail, but I believe it is, nevertheless, important. I also found that texture is not included in any other article about a type of mineral. Can someone please fix this problem? I am not entirely sure what the texture of Quartz is, so I don't want fix in case it is wrong. I was also checking out the composition of quartz, and I saw the composition, but not which elements were what. — Preceding unsigned comment added by $chavic (talkcontribs) 18:19, 4 November 2013 (UTC)


Hi Im not really sure how to sign posts on here but something else I thought was missing is. Does anyone know if quartz is capable of producing ionizing radiation which would mean either x or gamma rays? I know its piezoelectric and triboluminescent but is it also pyroelectric? And can this electricity manifest as radiation? Well apparently it can because it is triboluminescent. I read somewhere that all piezoelectric crystals are also pyroelectric but that there might be some slight exceptions, needs clarification. And Im also kind of curious what happens if you put electricity into a quartz crystal? Do you get heat and kinetic energy? like some sparks and the thing fracturing and flying apart? another thing that might be missing. Isn't quartz used in some infrared heating units? 96.42.117.51 (talk) 20:25, 25 August 2014 (UTC) Peter G.

Abundance of Quartz in crust[edit]

Quartz is a bit of a pain to write about. It's the most common mineral on earth, and occurs in so many different forms. The various names are used to mean different things in different contexts, and even then it's rarely rigoursly consistant.

I'll try and point out some of the range of applicability of the various names, and various applicable names.

Oh, and that density listed is not actually for quartz. It's for fused quartz, which is a glass - unlike every other type of quartz. I suspect that confusion is inevitable whilst it is shown on the main page for quartz.

Syntax 02 Jan 2004

Actually, quartz is not the most plentiful mineral on earth; that honour goes to plagioclase. I know what you're thinking: sediments (5% of earth's crust) are ~30% quartz, and granite-metamorphic rocks (~30% of earth's crust) contain about 10% quartz. Right? But feldspar is the predominant mineral in granites (at ~60% either plagioclase or orthoclase) is abundant in metamorphic rocks, is also present in sediments, and unlike quartz, occurs widely in the mafic and ultramafic rocks of the oceanic crust. So, bzzzt, quartz is evicted from the island. Rolinator 04:55, 7 February 2006 (UTC)
...although (just for fun) it does specify "continental crust" in the article.  :) By the way, for my own...er...interest, do you have a reference for your back-of-the envelope calculation? It sounds very much like you just whipped it off yourself (although good for you!) but if you have a ref that would be great. I have seen other numbers cited in German literature. Cheers,Rickert 07:09, 9 February 2006 (UTC)

Finch and Klein, 1999, The causes and petrological significance of cathodoluminescence emissions from alkali feldspars, CONTRIBUTIONS TO MINERALOGY AND PETROLOGY Volume 135, Numbers 2-3 (1999), 234-243, DOI: 10.1007/s004100050509 "Feldspar is the most common mineral in the Earth's crust." FWIW, there is almost no quartz in oceanic crust, but lots of feldspar. Text to be edited momentarily.Cwmagee (talk) 13:08, 20 May 2012 (UTC)

Citrine[edit]

Although most citrine occurs naturally, most is the result of heat-treated amethyst.

So, what is true about most citrine? Is most citrine natural, or is most citrine made from amethyst? Or is it natural-but-derived-from-amethyst-originally? This could stand to be reworded to be less confusing. -- pne 14:12, 30 Apr 2004 (UTC)

Fixed. Looks like that was a holdover from an wording change. Syntax 22:36, 1 Jun 2004 (UTC)

Varieties (add more)[edit]

Rose quartz, smoky quartz, aventurine, and citrine are all varieties that could use being listed in the that table.


Pleochroism[edit]

It's obvious that author of this article doesn't understand the meaning of pleochroism. Quartz has absolutely no pleochroism. I'll fix it. Siim 15:51, 7 May 2005 (UTC)

What is the difference between Quartz and glass?[edit]

I know that glass is amorphous SiO2, is the difference just in a macroscopic perspective of how the crystals are arranged, or is glas SiO2 non-polar while quartz is polar hybridization?

I'm not sure what you're asking here - do you want to know the difference structurally, or how to tell the difference? If you're talking identification, the best way to tell for sure is to chuck it under a petrology microscope and check to see if it's isotropic or not. If you're talking structural differences, well you're right - glass is amorphous at the atomic level - no regular lattice at all. Weebs 20:16, 15 October 2005 (UTC)
Technically, amorphous SiO2 is called fused quartz. Glass is a solid solution of SiO2 and other chemicals, such as NaO2. Both fused quartz and glasses are amorphous down to the molecular scale, with no 'grains' or microcrystals, which partly accounts for their transparency. --ChetvornoTALK 12:43, 25 June 2008 (UTC)

History of Quartz[edit]

"The exact date, place, and creator of the quartz oscillator are unknown to the public, as this information is classified. It is believed that it may eventually become public as the aftermath of the Cold War wears off"

- Walter Guyton Cady created the first Quartz crystal resonator along with other colleagues at Wesleyan University in Middletown, Connecticut in 1921
- George Washington Pierce also help future work in quartz oscillation by designing different types of quartz oscillators, 1923
- Warren Marrison, a telecommunications engineer developed the first quartz clock in 1927 based on Cady and Pierce's work at Bell Telephone Labratories

http://www.hrw.com/science/si-science/chemistry/careers/quartz/inventors/before.html

—Preceding unsigned comment added by 69.170.54.75 (talk) 23:22, 24 September 2006
Thanks, I have modified the article based on your reference. Vsmith 00:02, 25 September 2006 (UTC)

History[edit]

History The name "quartz" comes from the German "Quarz", which is of Slavic origin (Czech miners called it křem (should be Křemen, of I am not mistaken). Other sources insist the name is from the Saxon word "Querkluftertz", meaning cross-vein ore.

Crystal system -- hexagonal or rhombohedral?[edit]

The crystal system of quartz is rhombohedral according to fr:Quartz (minéral) (well I assume that's what "rhomboédrique" means). And sure enough, the Rhombohedral crystal system article does mention quartz as one example. Meanwhile, quartz isn't mentioned anywhere in the Hexagonal crystal system page. So is this article wrong in saying that quartz has a hexagonal crystal structure, or do hexagonal and rhombohedral mean the same thing? -- Sakurambo 桜ん坊 21:46, 5 December 2006 (UTC)

I went to the Wiki Quartz entry to look up synthetic quartz. The reference to hexagonal or six-sided jarred me. I had been through this before. Trigonal can arise out of cubic systems. Other piezoelectric crystals, perovskites for example, do that. Above the Curie temperature they are cubic and isotropic. Below the Curie temperature, the lattice distorts into the trigonal form and the crystals and become ferroelectric. If you were to look along a body diagonal of a cube, you would (orthogonally) project a hexagon. It is clear, however, that there is no six-fold symmeyry.

Hmm, i am not sure. I have a very reputable source here that says quartz is actually in the Trigonal - Trapezohedral system.... so i will have to do a little research and get back to this article. I always was taught it was hexagonal though. -- User:Chazparky 14:28, 17 December 2006

My copy of Klein - Manual of Mineralogy 20th ed, places quartz in the hexagonal system - but, according to the classification used therin, trigonal is part of the hexagonal system - and that is the way I learned it back in basic mineralogy (6 crystal systems with trigonal or rhomohedral as a part of the hexagonal system). Now for some detail: high quartz is hexagonal (class 622) whereas low quartz is trigonal (class 32). So I'd say some mention of this needs to be in the article for clarity as Wiki separates the trigonal from the hexagonal. Vsmith 00:33, 18 December 2006 (UTC)

I've got a copy of a fairly basic geochemistry textbook that says quartz's crystal system is hexagonal. It would help if someone could get a picture of the molecualr structure, especialy since its a pretty basic silicate mineral. -- User:Jason McConnell-Leech 14:54, 7 January 2007

Quartz is trigonal, also called rhombohedral, which is a sub-category of hexagonal, as Vsmith says. Klein/Hurlbut or Dana are appropriate references if one is needed. Kinda wondering why all the discussion about it, yet no change? My copy of Klein is in a box somewhere right now, but maybe I'll dig it out tonight.Olneya 22:50, 29 March 2007 (UTC)

I've removed the "Hexagonal" from the crystal system info for the sake of clarity. Following the link to the rhombohedral wiki will provide the information that rhombohedral/trigonal is a sub-group of the hexagonal system. I'm assuming it doesn't need its own ref, as there's a general ref to Klein/Hurlbut, and the info will be found there along with pretty much everything in the info box. --Olneya 03:50, 30 March 2007 (UTC)

Quartz is not rhombohedral. Low temperature (alpha) quartz is trigonal (space group P3_121). The trigonal system consists of primitive (P) and Rhombohedral (R) lattice types. If you heat it to ca. 573 C, it undergoes a transition to high (beta) quartz, which is hexagonal (space group P6_222). Judge Nutmeg (talk) —Preceding undated comment added 00:17, 19 March 2013 (UTC)

Flashing quartz Ute rattles[edit]

See Triboluminescence#Uncompahgre_Ute_Indians

Is the flashing caused by triboluminescence (cracks in the crystal structure causing electrical discharges from the triboelectric effect) or from piezoelectricity (deformation of the crystal creating voltages and causing electrical discharges, like piezo ignition)? See Talk:Ute tribe#Comment on piezoelectricity for discussion. — Omegatron 04:03, 26 November 2006 (UTC)

Ruby Quartz[edit]

Looking around the net I have found that the only place that ruby quartz displays the properties listed here is in the X-men comic book universe. Ruby quartz does actually exist, but with different properties. I'm not sure how to make this change, but I thought that it should be brought the attention of those who know. Thanks 68.102.208.72 04:37, 13 December 2006 (UTC)

Phantom quartz[edit]

For consideration as either a stand alone article, a Wiktionary entry, and/or a section in a longer article ... Recently added to Phantom, Phantom quartz, in response to the use of the term 'phantom' in the appropriate context in Herkimer diamond. Found external reference: http://rockhoundingar.com/quartz/types.html and http://rockhoundingar.com/quartz/phantom.html. --User:Ceyockey (talk to me) 01:07, 18 March 2007 (UTC)

Georgia's state gem...[edit]

Could someone possibly put in a reference to Quartz being the State Gem of Georgia? Probably in History, but maybe in a whole new area... ROBO 00:46, 16 May 2007 (UTC)

"quartzes" crystals[edit]

I removed the above as unlikely and uncited. Correcting nonesense 19:50, 31 August 2007 (UTC)

I don't know if it's correct. However, I've seen people called those crystal oscillators "crystals" (never seen "quartzes", though). Warut (talk) 11:45, 29 December 2007 (UTC)

Synthetic quartz image[edit]

Kevmin removed the synthetic quartz image by asserting that IMA has rules that man made materials are not minerals. I totally disagree with that and will bring back the image because this article is not meant to talk only about natural quartz. In fact, the image was placed next to the text that described synthetic quartz. Why removed only the image? Hopefully, this is not related to those recent anonymous edits on this image. Warut (talk) 22:59, 28 December 2007 (UTC)

While we may not like some of the rulings that the IMA has made since its creation in 1956(?), they are the overseeing body for mineralogy with the same authority as the organizations which oversee astronomy, chemistry etc.. and thus we are stuck with them until they are changed by the IMA itself. The picture was removed in part because of the trouble with the IP but also because it and the associated paragraph should be merged with the Chemistry article for synthetic quartz= Silicon dioxide. While a small section can be retained, most of the information is already present in Silicon dioxide or should be transferred.--Kevmin (talk) 00:19, 29 December 2007 (UTC)
I have updated the paragraph slightly with a link to the Silicon dioxide article, and have changed my opinion on removing the picture. Hope this is OK--Kevmin (talk) 00:26, 29 December 2007 (UTC)
Thanks for your explanation. I'd never known before that the use of the word "quartz" is actually limited to the naturally-occuring one since I often see things like quartz oscillators in clocks and quart window on EPROM. (Can someone else confirm this?) I had thought that its usage is like that of diamond, i.e., we can call anything diamond as long as its chemical composition and its atomic arrangement are those of diamond no matter how it's formed: natural or man-made. Warut (talk) 11:38, 29 December 2007 (UTC)

Removed Abbas Ibn Firnas Reference[edit]

The statement that 'Abbas Ibn Firnas was the first to produce glass from quartz.' is incorrect: he was credited for REGIONALLY developing a technique for grinding quarts -not making glass; furthermore, techniques for grinding quartz were already being employed elsewhere. That said, this information, while pertinent to Abbas Ibn Firnas and the history of the region in which he lived, is overburdening and off topic here. Mavigogun (talk) 07:27, 8 August 2008 (UTC)

Inappropriately Sectioned and unreferenced material[edit]

The following material was placed in the History section; while it may belong elsewhere, it is unreferenced:

'Quartz crystals are rotary polar (see rotary polarization) and have the ability to rotate the plane of polarization of light passing through them. They are also highly piezoelectric, becoming polarized with a negative charge on one end and a positive charge on the other when subjected to pressure. They will vibrate if an alternating electric current is applied to them. This proves them to be highly important in commerce for making pressure gauges, oscillators, resonators and watches.'Mavigogun (talk) 07:35, 8 August 2008 (UTC)

Age of Quartz Crystals[edit]

Is there any information regarding the average age of how long it takes for a Quartz Crystal to grow in nature?

Mrrealtime (talk) 14:42, 3 September 2008 (UTC)

There is some published information on quartz growth rate in vitro. Look it up. To make the question meaningful you would need to specify the conditions (chemistry, temperature, pressure) and the size of the crystal. Plantsurfer (talk) 16:24, 3 September 2008 (UTC)

I dont need to specify any of those things, but they should be part of the answer. I am looking for growth rates, the article should specify what kinds of conditions affect growth and how long it takes crystals to grow per given size (IE quarts grows at an average of at 1cm³/100 years, faster but less hard if xyz conditions are present, and slower but more uniform if xyz etc. ), I am here to find out that stuff, this is where I am "looking it up" so you, experts, tell me.Mrrealtime (talk) 13:52, 30 April 2009 (UTC)

Merge morion[edit]

I propose that the article on the mineral morion be merged into the table in the varieties section. The article is extremely short, and all of the information in the article can easily be integrated into the table (see below). There is also currently a dispute with the article Morion (helmet)

Major Varieties
Morion Dark-brown, opaque variety of smoky quartz resulting from irradiation of aluminium-containing milk quartz.

--Witan (talk) 22:47, 13 October 2008 (UTC)

That doesn't contain all the information from the article... consider adding natural or artificial before irradiation, assuming this is accurate and verifiable, for a start. But the pictures would still be lost. These can't be easily incorporated into the table, so we are still losing content. Are you sure the stub can't be expanded? Andrewa (talk) 19:50, 14 October 2008 (UTC)

Maintain support - "Natural and artificial irradiation" is redundant. How else can something be irradiated aside from either a natural or an artificial source? As for expanding the article, it's four years old and has had little information added after the first edit, and no new information has been added since the end of 2004 (with the addition of it being a variety of smoky quartz). I think it's highly unlikely that enough information will be added in the foreseeable future to warrant a separate article. As for the pics, three are not necessary to illustrate the concept, and one would easily fit in the gallery below the table, as was done for rutilated quartz.--Witan (talk) 23:48, 14 October 2008 (UTC)
The phrase natural or artificial conveys the information that both are possibilities. It doesn't imply that there's a third possibility. Perhaps it could be better put, but it's not redundant. Andrewa (talk) 00:34, 15 October 2008 (UTC)
"Superfluous" may have been a better word, but in any case we're down to talking about semantics here. Three more words still do not an article make, and I think they're unnecessary. Radiation is radiation is radiation, no matter its source. In any case, we're gonna have to wait for more people to weigh in to see what the consensus is.--Witan (talk) 01:46, 15 October 2008 (UTC)
Neither "redundant" nor "superfluous" - distinct and important for describing the mineral variety. Vsmith (talk) 02:21, 15 October 2008 (UTC)

Note the concurrent discussion on talk:Morion (helmet). Several editors have commented there and having two separate discussions about the "fate" of the morion article seem problematic as we now need consensus on two discussions. Anyone interested and commenting here should also take a look there. Vsmith (talk) 02:21, 15 October 2008 (UTC)

To further complicate the situation -- morion is a variety of smoky quartz or (smokey quartz) which would be a better merge destination. However, someone has renamed the general smokey quartz article to Cairngorm (mineral) - another local variety of smokey quartz. If any merge is to be done then the smokey quartz article should be revived and both varieties should be merged there. Are we having fun yet :-) Vsmith (talk) 02:35, 15 October 2008 (UTC)

Furthermore, as morion is simply a variety of a variety and most(?) is artificially produced it is definetly not a major variety. So, no to the merge proposal under discussion here. Vsmith (talk) 02:57, 15 October 2008 (UTC)

First off, it's the mention of the fact that morion can be created by natural or artificial radiation that is superfluous, not the fact that radiation must be used to create it. If it could only be created by artificial irradiation, or only natural irradiation, then the distinction would be important, but if any old radiation will do, then why mention that either variety will work? It's superfluous, like saying diamonds can be created by the natural or artificial heating and compression of carbon. Wouldn't it be simpler just to say it's created by the heating and compression of carbon? In any case, the fact about radiation is not cited, so we should start there.
Second of all, I saw the same thing with the smoky quartz article. Why someone would point a general article to a more specific example is beyond me, but that's how it is. If we want to merge it there, we'd have to revert that article back to what it was before. This thing is becoming more and more complicated all the time.--Witan (talk) 03:31, 15 October 2008 (UTC)
Also, take note Vsmith that the entry in the table for morion was already there. My merger proposal only suggests adding the rest of the information from the article into that section of the table, not adding morion to the table, so whether morion should even be listed as a major variety is a separate discussion...making this issue even MORE complicated x_x--Witan (talk) 03:36, 15 October 2008 (UTC)

Undid merge of morion into quartz varieties - not major and removed. I undid the caiengram/smoky quartz merge and revived smoky quartz. Merged both morion (mineral) and cairngorm (mineral) into smoky quartz. Made morion a dab page. What a mess that was. Fun & games, Vsmith (talk) 03:17, 21 October 2008 (UTC)

Merger proposal[edit]

Milk quartz, citrine and rose quartz
I have suggested to merge these three varieties since there is little to tell about each individually such as history, or use as gems, or mineralogical origin, specific occurrences etc.etc. Smokey Quartz was a borderline case in my opinion but then I saw the discussion and decision so I reset that proposal. However especially with White Quartz and Rose Quartz there is little to warrant an independent article as they are merely color variations without a significant history. Citrine I would argue is the same, although one could have a discussion about heat treated Amethyst. But this can easily be mentioned in the Quartz article and discussed more extensively in the Amethyst article, thus reducing Citrine to "merely" a color variety of quartz Gem-fanat (talk) 07:30, 25 November 2008 (UTC)

I'm in agreement. Adjusted headers above so merge proposal links here. Vsmith (talk) 22:58, 26 November 2008 (UTC)
Since there are no objections will move forward with merger in the next few days. Gem-fanat (talk) 21:49, 4 December 2008 (UTC)

Description of chemical formula[edit]

"It is made up of a framework of silicon-oxygen tetrahedra SiO4, with each silicon shared between two oxygens to give the overall formula SiO2."
Isn't each silicon shared by 4 oxygens within a tetrahedron and across tetrahedra each oxygen is shared by 2 silicon atoms? Since each oxygen in the crystal is really shared by 2 silicons, the O4 gets halved to O2 to give the formula of SiO2. If you're starting with the tetrahedral structure and you claim that each silicon is shared by 2 oxygens, you've contradicted yourself. The ratio of O to Si in the overall structure is 2 to 1, but by no means is each silicon shared between 2 oxygens. Go to http://cst-www.nrl.navy.mil/lattice/struk.jmol/sio2a.html right click on the figure, select style, label, symbol. You don't see any silicons shared by only 2 oxygens, but you do see lots of oxygens shared by 2 silicons. --Merlind (talk) 14:03, 31 May 2009 (UTC)

I agree, sounds bogus. If the chemical formula is SiO2 (giving the correct elemental ratios), then the lead shouldn't precede this by calling quartz SiO4. Moreover, I don't know if there is any justification whatever for saying SiO4 ever (since while this may be an element in one description of the structure, we could potentially describe the structure in another way using a third psuedo chemical formula). Better to just say it is SiO2, it's structure is blah, and then further down when giving more detail about the structure, then MAYBE you could say that the structure can be simply visualised in terms of SiO4.. but only if there are references to support using this notion, because unless it is standard it just looks needlessly confusing and possibly technically invalid. Cesiumfrog (talk) 07:39, 4 December 2010 (UTC)

The number of oxygens around Si (in SiO2) and the chemical formula are not related at all, and this is common for any solid, as atoms are shared to a different degree. For simplicity, take cubic NaCl. Each Na is surrounded by 6 Cl atoms .. Materialscientist (talk) 07:57, 4 December 2010 (UTC)

I think the lead should be changed: It should not start with the statement of it being "second most abundant mineral" because that ranking is not only uncited but also fundamentally unscientific (see Talk:Feldspar#abundance for problem); an alternative option is to lead with the percentage abundance, or with the fact that it is the most stable [2] form of silica. The first or second sentence should be "Quartz is a type of silica; the chemical formula of Quartz is SiO2 and it consists of almost equal weights of oxygen (53%) and silicon (47%)." Then, follow with the technical detail which distinguishes quartz specifically, making sure to emphasise the structural components are not independently real, just convenient for us to use. "The structure of quartz can be visualised as composed of a network of SiO4 tetrahedra, with each oxygen atom shared between two tetrahedra. The crystal is made of a repeating unit cell which contains three of these tetrahedra, and can be expressed (SiO4/2)3. These tetrahedra are arranged in helixes down the axis of the crystal, which effects its optical activity. (cite quartzpage.de)" The later subsection on structure should also mention how the tetrahedron geometry is almost ideal, but the angle of the oxygen bond is far from straight, in fact it is 144 degrees (cite quartzpage.de more). Also, the image for beta-quartz is almost certainly wrong, because its ratio of oxygen atoms is seemingly twice what it is supposed to be (almost as if some poor foo' read the current lead, which starts by giving the formula SiO4, and mistook it at face value). Cesiumfrog (talk) 05:07, 16 December 2010 (UTC)

Just a quick reply on "the image for beta-quartz is almost certainly wrong" - (i) please re-read my previous comment before throwing out such statements, and try to understand (or accept in good faith) the concept of atom sharing. (ii) the beta-quartz image is additionally complicated by showing, in one unit cell, several possibilities of atomic positions which are realized in that crystal. If you click the image, you'd notice that some atoms are sort of blurred or doubled. They can't be that close to each other - these are atoms from different crystal cells, projected into one cell. This is common for crystallography, but might be a bit confusing to those who count atoms. Materialscientist (talk) 05:30, 16 December 2010 (UTC)
So I take it the diagram is not showing the unit cell then? Cesiumfrog (talk) 08:34, 16 December 2010 (UTC)
Those are unit cells, but not really the primitive unit cells (i.e. the smallest possible units required to build up the crystal), again because of sharing, which is different for atoms at the cell edge and "inside" the cell. Some software was even designed to cut shared atoms in segments to account for that sharing (i.e presenting a corner atom not as a sphere but as its quarter, 1/6, or etc.) Materialscientist (talk) 08:45, 16 December 2010 (UTC)
Then why are there multiple overlaid possibilities? Is it a quasicrystal? Cesiumfrog (talk) 11:12, 16 December 2010 (UTC)
No, it means in some parts (of a perfect crystal) that "doubled" atom is in one position and in other parts - in another. Materialscientist (talk) 11:23, 16 December 2010 (UTC)
I thought there were only two cases: either the various (two?) possibilities are alternated in a repeating pattern across successive cells, in which case the true unit cell is actually larger than the box shown, or else the various (two?) possibilities are alternated randomly, the quasicrystal case. Is there a third option, or could you try explaining again? Cesiumfrog (talk) 11:40, 16 December 2010 (UTC)
The positions are random across the crystal, but this is not called quasicrystal. Such split positions are not unusual, and this article, for example, deals with more complex cases (partial occupancy, etc.) Materialscientist (talk) 11:55, 16 December 2010 (UTC)

herkimer dimonds[edit]

do you know anything else about herkimer dimonds? —Preceding unsigned comment added by 68.10.196.244 (talk) 22:16, 26 August 2009 (UTC)

herkimer diamond can be very clear you can see out out of them. —Preceding unsigned comment added by 68.10.196.244 (talk) 22:18, 26 August 2009 (UTC)

Prasiolite[edit]

I have added a merge to tag to Prasiolite as it is a little known varietal name and not likely to get beyond stub. --Kevmin (talk) 20:54, 4 October 2009 (UTC)

Support merge. Vsmith (talk) 22:07, 4 October 2009 (UTC)

I wil try to add more info. i think it should have it's own page. It's just my opinion but i also think citrine, rose quartz and smokey quartz should have their own page. -Humanfeather (March, 13th 2010)

Smoky quartz[edit]

Shouldn't the image of smoky quartz be further down the page where the text for smoky quartz is? While reading the article I was confused as to whether smoky quartz might have been a variety of the type of quartz which text it was listed by. I'd do this myself but I am not proficient at moving images around on WP pages yet. Thomas R. Fasulo (talk) 14:58, 1 March 2010 (UTC) What is the value of the quartz cbucrystal —Preceding unsigned comment added by 71.142.90.247 (talk) 16:41, 8 May 2010 (UTC)

Major varieties of quartz[edit]

currently contain dumortierite quartz and rutile quartz. Not sure about quartz, but in diamond, inclusions of a foreign phase do not create a new variety. Materialscientist (talk) 22:30, 22 July 2010 (UTC)

Varieties to rock shop/mineral dealers perhaps like most of the "heat treated" amethyst colors - $$$ from the pockets of crystal power folks and such. If we were to demand scholarly refs for those "varieties" methinks it'd be hard to find. Hey - go for it :) Vsmith (talk) 23:53, 22 July 2010 (UTC)

Copyright problem removed[edit]

Prior content in this article duplicated one or more previously published sources. The material was copied from: http://www.galleries.com/minerals/silicate/quartz.htm. Infringing material has been rewritten or removed and must not be restored, unless it is duly released under a compatible license. (For more information, please see "using copyrighted works from others" if you are not the copyright holder of this material, or "donating copyrighted materials" if you are.) For legal reasons, we cannot accept copyrighted text or images borrowed from other web sites or published material; such additions will be deleted. Contributors may use copyrighted publications as a source of information, but not as a source of sentences or phrases. Accordingly, the material may be rewritten, but only if it does not infringe on the copyright of the original or plagiarize from that source. Please see our guideline on non-free text for how to properly implement limited quotations of copyrighted text. Wikipedia takes copyright violations very seriously, and persistent violators will be blocked from editing. While we appreciate contributions, we must require all contributors to understand and comply with these policies. Thank you. VernoWhitney (talk) 17:42, 22 December 2010 (UTC)

Missing closing parenthesis[edit]

In introduction, please fix: "The word "quartz" is derived from the German word "quarz", which was imported from Middle High German, "twarc", which originated in Slavic (cf. Czech tvrdy ("hard"), Polish twardy ("hard").[6]"

I'd do it myself if it weren't locked. -- 77.189.42.230 (talk) 16:27, 20 February 2011 (UTC)

Corrected. The article is not locked. Materialscientist (talk) 23:50, 20 February 2011 (UTC)

Re-organize and partial re-write underway[edit]

In response to a question on my talk a re-write/re-organize of the page is underway. Progress may be slow ... as time allows. It has been suggested that the ====Gemstone and lapidary varieties==== section (recently re-titled) should be moved to its own article. As the page grows that may be an option, but for now perhaps the section (scaled back and with fewer images) should remain under a uses section, but should not dominate the article as it had previously. Vsmith (talk) 16:20, 18 August 2011 (UTC)

Healing properties[edit]

Should there be a mention of the healing properties of quartz seeing as it is regarded as the best healer of all crystals? — Preceding unsigned comment added by 213.41.212.2 (talk) 16:21, 19 January 2012 (UTC)

Quartz does do a good job of "healing" or sealing fractures in rocks when deposited by hydrothermal solutions - resulting in hard quartz veins. Considered thusly, I'd guess it is good at "healing" other rocks. Vsmith (talk) 16:36, 19 January 2012 (UTC)

You haven't understood the question !! — Preceding unsigned comment added by 109.10.108.248 (talk) 17:52, 19 January 2012 (UTC)

Well the only other meaning of the original question would refer to the use of quartz crystals to in treating health problems, for which there is no evidence whatever; unless that's why if feels good to lie on a sandy beach. Mikenorton (talk) 20:20, 19 January 2012 (UTC)

Well, I didn't say that there was any proven scientific 'evidence' for it, just that quartz IS USED for that purpose by many people and could be mentioned (hard science does not have the monopoly on crystals !!). There is an article called 'Crystal Healing' on Wikipedia anyway so it's not a problem. Cheers. — Preceding unsigned comment added by 109.10.108.248 (talk) 09:23, 20 January 2012 (UTC)

Indeed crystal healing and is a folk use and it belongs on this article because wikipedia is not merely a scientific organization there is much to be learned about history on here as well. I am writing my own article for an amethyst on <spam link removed>.

I can point out countless articles about herbs and plants on wikipedia which include outdated and "scientifically doubtful" folk uses. Some of which are actually quite toxic but none the less the folk use is mentioned. If people used the herb for arthritis, got sick and died and their arthritis actually worsened it is mentioned because that's reality. Also quartz is capable of developing an electrical potential when exposed to even small amounts of heat radiation resulting in an increase in temperature which inturn causes a pyroelctric effect does it not? There is too much about the body that is electrical to be ignored. I am also not aware of any study proving crystal healing to be ineffective. There was a study done by Dr. Cristopher French at Goldsmiths College, London in which they proved that volunteers given a fake were succeptible to a placebo effect but this simply proves that placebo effects exist.

It does not prove that quartz crystals have no effect. The real effect (if it is real) could be identical feeling to the placebo effect and therefore impossible to prove or disprove.

In fact many crystal healers believe in "programming" objects with their "intentions". Supposedly this is what quartz amplifies and it could even be an enhanced placebo effect giving not only all the

wonderful health benefits of the placebo effect but also electrically balancing the body. The volunteers experienced varying sensations from what the study concludes as “power of suggestion.”

In other words, the human mind is capable of creating physical change in the body, simply by the mind itself “suggesting” it.

That is what quartz supposedly amplifies. I have not claimed to prove quartz healing to be effective even as a gradual process but you are a long way from disproving it and it is a folk use. The whole thing could devolve into a debate about quantum mechanics and energies you cant measure as I dont believe quantum mechanics are fully understood anyway. -- Peter Grinsell from <spam link removed> — Preceding unsigned comment added by 96.42.117.51 (talk) 22:55, 10 August 2014 (UTC)

Any such would belong at crystal healing with appropriate WP:reliable sources. Vsmith (talk) 00:16, 11 August 2014 (UTC)

well the article should mention that quartz is used for crystal healing with hypertext -- Peter G. — Preceding unsigned comment added by 96.42.117.51 (talk) 22:11, 11 August 2014 (UTC)

Citrine[edit]

citrine should be a full article disable the redirect O0fishguy0o (talk) 06:09, 3 September 2012 (UTC)

It's a variety of quartz, the redirect is ok, nobody had the time to create an article about citrine yet ;) --Chris.urs-o (talk) 07:49, 3 September 2012 (UTC)
It was a stub prior to the redirect on 11 Dec 08. If the short section grows - it can be re-instated as an article. Do you have good sources to expand the citrine section? Vsmith (talk) 13:28, 3 September 2012 (UTC)

Largest crystals[edit]

I came to the article looking for information on how large natural quartz crystals can grow and where these might be found and found nothing. Can somebody add something? 79.79.249.242 (talk) 10:21, 7 March 2013 (UTC)

Roughly 6x1.5 m, see p. 903 here. Materialscientist (talk) 10:29, 7 March 2013 (UTC)
Like Plantsurfer (talk) 11:02, 7 March 2013 (UTC)
Planggenstock crystalsNatural History Museum of Bern: 300 kg, 107 cm (central crystal). --Chris.urs-o (talk) 11:16, 7 March 2013 (UTC)

Pyroelectricity[edit]

This article does not mention whether quartz has pyroelectric properties and I have been hard pressed to find out if it does. -- Peter G. — Preceding unsigned comment added by 96.42.117.51 (talk) 23:19, 12 August 2014 (UTC)