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Quartz

Posted by Stephan Segedy  
Quartz
August 18, 2011 08:50PM
I suppose it is inevitable that a mineral having as many varieties as quartz will be prone to naming conflicts.

Recently there has been some discussion around "Star" Quartz, a varietal name for fan like radiating aggregates of quartz, noted as not to be confused with asterism, an optical property. "Asterated Quartz" is also listed as a synonym for this variety.

The problem is that both these terms are in practice also used to describe minerals which exhibit asterism. I have seen the term "asterated" as well as "star" applied to both Rose Quartz and Idaho garnets having asterism.

The confusion may have arisen for geographical reasons. The best specimens of Star Quartz have come from Europe, while the use of these terms for asterism may be a US phoenomenon. Not sure.

I believe "asterated" to be a more venacular form of "asteriated". The majority of online dictionaries I perused described "asteriated" as meaning asterism, but, to complicate matters further, I have found at least one online dictionary that ascribes both meanings to this adjective! (http://www.yourdictionary.com/asteriated).

Asterated appears to be most commonly used within the context of asterism - at least outside of the Mindat community.

Confusion is already occurring in our database. As I peruse the localities attributed to "Star" Quartz, I think some of these are localities for Rose Quartz exhibiting asterism? (Bedford, NY comes to mind ).

I am not sure whether varietal names based on optical characteristics are allowed?? If not these should be culled from the locality list for the aggregate variety. But to do this might incur the loss of potentially valuable info regarding the locality, unless the presence of asteriated quartz were duly noted in the locality description.

If varietal names based on optical characteristics are allowed then I would suggest adding a separate variety of quartz, or perhaps a sub-variety (of Rose Quartz) known as Asteriated, to allow an alternative rubric under which to classify these. I would further suggest that we might consider dropping the term "asterated" as an alternative name for "Star Quartz" in order to avoid confusion.

There is provenance for the term "asteriated" dating at least back to early 1900s to describe the asterism of Rose Quartz of Bedford, NY (an occurrence which probably should be reclassified)
"Asteriated rose quartz in NY" : Min. World, June 11, 1910, pp. 1185-1186 James G. Manchester

I have a vested interest in seeing this terminology resolved as I like my labels to match what is on MINDAT.

What do others think??

Thanks,
Stephan
Re: Quartz
August 18, 2011 11:33PM
So what shall we do with star sapphire and star ruby (in the name of consistency)?
"Asteriated sapphire" will not sell ;)
"Star rose quartz" also sounds much nicer.
Tthese are all compound terms of the form "variety of ( variety of mineral)"

You could name quartz crystals radiating from a common point a "quartz star", that will give most people a good idea of what it looks like (this term is in fact occasionally used).

Or you could name quartz crystals radiating from a common point "quartz crystals radiating from a common point".
That would be a lawyer's choice.


Stephan Segedy Wrote:
-------------------------------------------------------
> I am not sure whether varietal names based on
> optical characteristics are allowed??
The drop down list for selecting varieties in the photo upload form contains both color varieties and - unfortunately - form varieties (capped quartz etc.) and stuff I've never heard of.
Personally, I'd rather see the shape/form varieties removed from the list.
Re: Quartz
August 19, 2011 05:00AM
Points well taken - I think this is a special case where optical characteristic and shape/form are similarly described, and the optical description has been historically treated as if it were a de-facto varietal. Not unlike mineral names that are grandfathered due to historical usage.

It raises the thorny debate whether or not such characteristics are truly varietal, does being able to track/correlate these characteristics and the environs in which they occur further enhance our understanding of the mineral and it's morphology, and is Mindat the best place to do so?

A discussion worth having, but for now I will be content to simply disambiguate the information already in the database! :)
Re: Quartz
August 19, 2011 10:58AM
Minerals are classified/defined by a specific limited set of properties, basically chemical composition and structure (the way atoms are arranged in the crystal). These mineral definitions (sets of properties) are mutually exclusive: one mineral cannot be another, even if a single crystal may contain different minerals.

Varieties, on the other hand, are defined by properties that specimen have in addition to the set of properties that determines how they are classified as minerals. There's no limit on the number or type of properties. Color, shape, feel, everything goes, and can be mixed, as varietal definitions are not mutually exclusive: a sapphire can be asteriated just as a ruby, an amethyst can also be a smoky quartz.
Variety names are given for practical considerations (making communication easier, help theory building, help selling stuff), and most of the names come and go. There are no (and should not be) rules or classification schemes for varieties.

One could only ask to clarify general terms used to define varieties, like "asterism", "dichroism" etc. But I don't think there are too many errors about these terms on mindat.
Many errors on Mindat are indirectly caused by the improper use of the term "synonym", so if you want a mental work out, try to get the management to fix this :D
I've given up.
Re: Quartz
August 19, 2011 09:42PM
Since both, star, and asterism are directly loaned Greek words you should be looking for another original greek word to describe the quartz shape. What you are searching for is " Asterioides " (not asteroides obviously) which means with the shape of a star, widelly used in flora terminology. Sorry but asterated and asteriated sound way too funny at me, since the use a greek origin (star) and create a new english type term, like saying for example gwindelated quartz!



Edited 1 time(s). Last edit at 08/19/2011 09:45PM by Athanasios Ziros.
avatar Re: Quartz
August 20, 2011 11:17AM
Certainly a word can have more than one meaning. Its quite common in English. If we develop a glossary of mineralogical terms, we can list more than one meaning and in each different meaning for a work we can make clear how it differs from the other(s). This is probably better than trying to create our own words or limit the meaning of a word to only one definition.

Rock Currier
Crystals not pistols.
Re: Quartz
August 25, 2011 06:18PM
Agree with some caveats -

In conversational English we can usually deal with ambiguity in terms or expressions by deducing meaning based on its context.

In science, we may already be operating within a narrow context (such as mineralogy), and so have less latitude for vagueness.

In systems and databases, such as MINDAT, it is critical to use unique terms or expressions for identifiers, as these are the "indexes" or "handles" by which we store and retrieve data. Additional synonynms are fine, as long as each is unique, and returns only the data to which it pertains.

I would not be averse to modifying the existing categories to: "Star Quartz (aggregate)" and "Star Quartz (asteriated)" <or alternatively (optical)> with appropriate synonyms.

I would like to see "asteriated quartz" in there at least as a synonym, and since most of the occurrences described are probably rose quartz, I would like to see an entry for "star rose quartz (asteriated)" or "asteriated rose quartz" as a sub-variety of rose quartz. But, terms aside, the objective is there must be a differentiation!

As you may have gathered, I still prefer the term "asteriated", as this is how I have always heard the optical phenomenon described among those whom I consider knowledgeable. As illustrated above it has been around for quite a while.

How this began: I was researching the aggregate variety of star quartz and it's environs, but soon became frustrated when looking at the occurrences for the reasons stated above. I'm keenly interested in better understanding the formation of these aggregates. I also suspect the phoenomenon may be more widespread than has been so far recognized and reported. perhaps differentiation will encourage additional reports. A good segue' to get back on topic:

This issue only affects a small data-set within a small microcosm of the database. It will be a good time to set things on the right track before
additional data gets entered and the waters get muddier (build it and they will come). Folks are posting asterism as a variety and need better place to put these, and I am sure that once these varietals are elucidated, not only will contributors begin to put new occurrences under the best heading, but also, existing ones will migrate appropriately.

The first step is to provide the appropriate infra-structure - can one of the avatars make this distinction a reality?

Thanks,

Stephan
Re: Quartz
August 26, 2011 12:01AM
I agree that a good technical terminology is necessary for a scientific discussion, in particular when it comes to discussing the formation of things.

But the proper definition of something will not keep people from selecting what they think is right from the list and you will still have all sorts of images which show something that is different from the stuff in the definition.
If you want them to do what you think is the "right" thing, you'd have to get them fix it to your liking - write an error report "photo ID 123456 is not a bull quartz blah blah" and discuss it.
And you know, these collectors all have their pet topics :D

And to have something like "starbrary quartz" and other nonsense as an individual database entry (min-28986.html) is simply crazy. That way it ends in the drop down menu for the photo descriptions and people are encouraged to use such terms.

I would really like to see all these speciality terms removed, including "star quartz". Only well-established and commonly used variety names deserve to be offered as a choice. One can still put any varietal name in the text description.

I understand that one would want to give good answers to questions like "what is girasol?".
But the answers should go into a glossary.

BTW, I'd say there are only three (3) varieties that people agree upon: rock crystal, amethyst, smoky quartz.
For all the others, people will get into a fight over the proper definition.

And there are some more important structural "varieties" of quartz that are somewhat "fundamental" but difficult to understand (and determine), like macromosaic quartz, quartzine, microquartz, etc.
So far we've been lucky: nobody cares about them. :D



Edited 1 time(s). Last edit at 08/26/2011 12:02AM by Amir C. Akhavan.
Re: Quartz
August 26, 2011 03:20AM
Amir,

Don't most people agree on milky, citrine and rose? I see quartz var. milky often.

Regards,
Mark
Re: Quartz
August 26, 2011 03:49AM
Milky seems a pretty stable term, but citrine and rose suffer from some complications. Citrine is used for genuine yellow quartz, but some use it also (erroneously?) for quartz colored by extraneous yellow iron oxides, or for artificially burnt amethyst. Rose quartz comes in two types, a massive one colored by nano-inclusions of a dumortierite-like mineral, and crystals with chemical substitutions 9phosphate plus something else; I forget). Some people suggest calling the latter type "pink quartz", to differentiate it from the better known massive "rose quartz". Like Amir said, there's no shortage of people who will passionately dispute whatever you decide about varietal names.
Re: Quartz
August 26, 2011 08:52AM
Some authors use milky quartz for vein quartz only.

Pink: yes, it's P and Al in color centers, apparently requires irradiation like smoky and amethyst, it's light sensitive, dichroic, and a late stage (and probably medium/low temperature) pegmatite formation. 99.9% of the images labeled "rose quartz" on Mindat show this type.

Citrine is a real mess. Just for starters, there's not only quartz with extraneous iron oxides, a lot of times the inclusions of iron oxide/hydroxide minerals are, well, included. Which makes them "ferruginous quartz". Burnt amethyst is an example, the "citrine" sectors in ametrine are ferruginous quartz, too. Ferruginous quartz is not a term people agree on either, of course. There's a lot more confusing about citrines. To me, citrine and smoky quartz go into the same basket :P.
Re: Quartz
August 26, 2011 09:58AM
Asteriated means "Star like"......
Re: Quartz
August 26, 2011 01:26PM
us    
Amir

I still find this one most interesting
© Brian Kosnar


Wayne



Edited 1 time(s). Last edit at 08/26/2011 04:10PM by David Von Bargen.
avatar Re: Quartz
August 27, 2011 01:25AM
That's a wonderful picture of ametrine and when I get around to doing Best Minerals Quartz Bolivia, If I can't hornswaggle Alfredo to do it first, I will definitely put that image in the article.

Rock Currier
Crystals not pistols.
Re: Quartz
August 27, 2011 01:10PM
I've labelled the specimen in the attached photo (from the Ohio Mine, Ouray, Colorado), Quartz var. Milky. Is that wrong? If so, then what is it?

Mark
Attachments:
open | download - IMG_4369.jpg (651.1 KB)
Re: Quartz
August 27, 2011 03:21PM
us    
Mark

Your correct.
Tho,, I know this variety as "Corncob Quartz" , often found at Diamond Ledge, Stafford, Tolland Co., Connecticut, USA also.
Stafford CT. Corncob Quartz

Wayne
Re: Quartz
August 27, 2011 03:52PM
Mark & Linda Mahlum Wrote:
-------------------------------------------------------
> I've labelled the specimen in the attached photo
> (from the Ohio Mine, Ouray, Colorado), Quartz var.
> Milky. Is that wrong? If so, then what is it?
>
> Mark

No, it's very right ;)
It's milky quartz.
Really nice Ouray specimen, btw.

It's also a cactus quartz.
Others would call a cactus quartz a spirit quartz.
And again others ananas quartz.

Maybe that's a good example: Because I helped at the exhibition in Lwowek Slaski, I know that ananas quartz is something else in Polish (I forgot what, sorry :P )
I learned that all the gem variety names (amethyst, chrysoprase, etc.) are easy to translate, I can even read them in Polish, surprise, surprise :D (people want to know what they get for their money).

But when it comes to shapes of crystals and aggregates, this simply does not work. I remember lengthy discussions on how to translate "split growth" and how to explain the quartz growth forms that are based on it. It is simply a meaningless term in Polish. I have to admit, I can't even say what split growth is in German :S .


I only said that there are only 3 variety definitions that people basically agree on.
I did not mean to say it's wrong to use the other variety names.
I do that all the time, here's a milky quartz with split growth: [www.mindat.org]

I only think it's not a good idea to have all these varieties as choices in the photo upload form, and also not a good idea to have individual pages for all of them.

Of course, a nice thing about the variety in the title is that for many localities it is a pain to go through all the different quartz photos just to look for an amethyst. It's nice that you can click on the photo icon left of the "quartz var. amethyst" entry in the list of minerals.
avatar Re: Quartz
August 12, 2012 12:04PM
gb    
I have decided that i will not try to add citrine to my collection because i think it is impossible to tell if from ferruginous or iron stained quartz, at least visually. maybe it can be distinguished with a SEM or XRD testing, unfortunately i dont have access to those so it is not really worth getting citrine.
I dont even think testing with iron out can be conclusive and even if it were its unavailable in the UK!
Re: Quartz
August 12, 2012 04:57PM
No, it is not difficult to tell citrine from ferruginous quartz or iron stained quartz:
Non-destructive test: citrine is dichroic.
Destructive test: citrine will pale when heated above 200-300 deg C. It will also pale in UV light, but i would not have the patience for such a test.



Edited 1 time(s). Last edit at 08/12/2012 07:22PM by Amir C. Akhavan.
mckyndal calhoun
Re: Quartz
March 27, 2014 04:40PM
Quartz is a very pretty mineral and has a lot of history.we should all have a book about quartz because we need a little knowledge about this topic.



Edited 1 time(s). Last edit at 03/27/2014 05:44PM by Uwe Kolitsch.
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