Pseudomorphs & Replacements A & B

Rock
Don't know if this is what you are looking for?

GLENDONITES
The large group of Worldwide Calcite pseudos, NOW known as "Glendonites", have been described under a variety of different individual names, as will as being assigned various parentage. Many were consolidated under the name "Pseudogaylussite"(Von Calker 1897). However E. S. Dana(1884) while studing similar Calcite pseudos from Nevada, believed the precursor would be a mineral yet to be discovered. That material was finally located in a Greenland Fjord(Pauly 1963). It proved to be a thermally unstable, Calcium carbonate hexahedrite. He named it Ikaite, after the fjord. As it was a massive mineral, it did not create much interest among pseudo collectors, except in Russia(Kaplin 1978). The first Ikaite crystals were found in drill cores, extracted of the Bransfield Strait, Antartica. At tenperatures above 4-5 degrees Celsius, the Ikaite separated into a "Mush" of tint Calcite crystals and water. Suess(1982), on the basis of crystal shape and the alteration to Calcite, declared Ikaite to be the missing precusor for this group of pseudomorphs. He refered to the pseudos as being "Glendonites", a term being used for specimens of this type from nearby Australia.

Hi Rock and all,

The article is going well I see.
Interesting stuff.

There is just a little error in the Chalcosite after wood from Clay Co. Texas. The name written is Chalcosie.
I also saw that the Ankerite after Calcite from Sainte Marie that I submitted, is missing.
With all the work you have it must have slipped thru the canvas.
Nothing personal if you dont include it.
I hope this helps.

Take care and best regards.

Paul.

Kieth, That is exactly the kind of stuff I am looking for. I wonder if I might tempt you to add a second paragraph bases on your own extensive experience about, where the best glendonites come from and how big they get and how many of them there out there and why we don't see many of them offered for sale etc. Could you add some comments about the double pseudomorphs of opal after calcite after Ikaite. We don't have a specific section on glendonites in the pseudomorph articles but show them under Calcite after Ikaite. I was thinking I might use what you write about them and place it in two places. Once in the lead in commentary about Calcite after Ikaite and also in the section after the Quartz, var. opal after Calcite after Ikaite from Australia.

I have taken a bit of a break from the Pseudomorph articles here on mindat. I have discovered that there were a whole slew of good pseudomorphs in our galleries by searching on the keywords replacing and replaced and altered and altering and I must now also integrate them into the articles which will require a lot of time. I have also gotten side tracked by trying to photoshop all my various locality images taken during my 30 or so years traveling around here and there. There are still thousands left to photoshop and it will probably take me another couple of weeks to get that done. Then there will be the task of uploading those to mindat. Jordi Fabre wanted some pictures to add to his translation of that bit I did about mineral collecting and then I thought I should post that as an article here on mindat and add a bunch of locality pictures to it and that got me trapped in my current obsession to finish the photoshopping of my locality pictures. But when I finish those, Ill get back and start hammering away at the pseudomorph articles again.

I was hoping I could get you interested enough to help and perhaps even take over the construction of what has become a much bigger job than I thought it would be about pseudomorphs. You know more about pseudomorphs than anyone I know and would be the ideal person to do this.

Rock Currier
Crystals not pistols.

Paul,
Thanks for the correction on the Chalcocite error. You only found one error? I must be getting better as I get older or you are getting worse certainly you can do better than that!

I have added the Ankerite after calcite. Can you tell us how many of these were found and roughly when. Only from one mine? Is the one you posted about at good as they get?

Rock Currier
Crystals not pistols.

Hi Rock,

Thanks for the reply.

I wrote a comment on the first page of this topic. That's all I have for the moment.
When I will have more time, I will dig all my information up and add it here.

I hope this helps.

Take care and best regards.

Paul.

Paul, When you say you wrote a comment on the first page of this topic, could you give me the URL of that page?

Rock Currier
Crystals not pistols.

Hi Rock,

Made a copy of what I wrote.


It is deffinately ankerite after calcite. Many test where done on these and the more recent by Fluck and Bari in 1982 and later on.
These are well known in the district since centuries. They are part of the " paragenèse à carbonates nobles " ( nobel carbonates paragenesis ) which is the paragenesis of the veins. The native silver and silver minerals from the district were always found near these pockets and IN this paragenesis.
At the museum at Ste Marie there is(was ?) a chalcopyrite crystal cluster with these doubly terminated pseudo's to 6 cm cris-cross over them. I saw that piece back in 78 and still dreaming about it.

What I find interesting about these pseudo's is that the original form of calcite ( the scalenohedron ) nearly completely dissapeared from the district except from 2 mines ( according to my observations of the specimens in many local collections and books on the district ). All the other calcite who was formed later, is from the " joplin" type or simple rhombs. The scalenohedron is observed in the Toussaint mine and in the Glück auf ( see my gallery ). I saw in 1987 in a local collection such a double terminatated pseudo af ankerite after calcite on matrix sparkled with very tiny gemmy double terminated joplin calcites. Just amazing. The collection has been dispersed whem the owner passed away in that same year. No idea where the specimen went. It would be great to find that piece back and take a pic of it and post it on Mindat.

I hope this helps.

Take care and best regards.

Paul.

Paul,
That is exactly what I was looking for. I have tweaked the English a bit and placed it in the article under the pictures of Ankerite after Calcite from France with your name and the year you wrote it, (this year) at the bottom. You should read it over and make sure I have not changed anything important.

Rock Currier
Crystals not pistols.

Rock, when you get back to this article there are a few misspellings I noted

Analc[ite] after Analcime and Siderite

Bavenite afer Beryl

Baventet after Beryl

In the paragraph after Calcite after Glauberite
"have been artificially died"

In the description of Carmenite after Balydonite
"1 mm balls or Carmenite"

Blame it on the editor in me.

Easy Goin'
USA



Edited 1 time(s). Last edit at 04/22/2011 03:25AM by Ed Godsey.

Ed,
Thank heaven someone is reading this stuff with a critical eye. Thanks for the corrections. They have been made. How would you like to take a crack at a best mineral article. If so, I would suggest something not to ambitious to start with, or perhaps one of the minerals like quartz, calcite, gypsum or fluorite from a single country? If so, let me know and Ill help you get started.

Rock Currier
Crystals not pistols.

Rock
Will expand the info on Calcite pseudo Ikaite. Can also include notes on several of the photos, as many of the pseudos had individual nanes.The specimens labled as being after Gaylussite, can be left in place. Just note that they have now been reclassified as being after Ikaite. Did not find new photos of Calcite after Gaylussite posted.

I concocted a skeletal outline of a Pseudomorphic Classification, to including: Molds & Casts, Incrustations(Epimorphs etc.), Substitution,
Structural Alterations(Paramorphs) Hybrid Structural Pseudos(Uralite, Metamict & Exsolution Types) Chemicall Alteration(By Loss, by Gain &
Partial Exchange of componants). How detailed do you want the explainations to be?
Keith

Kieth,
To be honest, I don't know how detailed it should be. How much of what you have in mind for a detailed description has been written about before? How much will the casual reader of these articles be able to absorb? How much will the person who is interested seriously in pseudomorphs be able to absorb? I suspect that only the feed back by the people who use these articles will be able to eventually tell us these things. Keep in mind that whatever we do here may eventually be subsumed into some sort of database that can be searched in different ways to discover relationships that we are not yet aware. I suggest you write something as detailed as you can stand and if we ultimately discover it is too complex it could stand as a separate article and parts of it can be used in the introductory section for the pseudomorph articles with links that people can click on to take them to the main article or parts of the article that they are interested in. You might pick one type of pseudomorph for a detailed treatment and we can load it up here and request comments from the mindat community about if it should be simplified or not and that may give us a direction about which way to proceed.

I don't think there were any new pictures of Gaylussite after Calcite posted in the pseudomorph article and it is not clear from you post if you saw the currently posted ones, but they are in the calcite section of the Pseudomorphs A to C. If you agree that they are after Ikaite, I think it best that the captions should be changed so that they are shown as Calcite after Ikaite with an explanation below the pictures that they, as others of this kind were commonly described as Calcite after Gaylussite or Glauberite etc.

What ever notes you would care to add to the various images of pseudomorphs would be welcome, and Ill see that they are inserted below the appropriate images with a credit to you.

Rock Currier
Crystals not pistols.

Here is one of my many pseudomorphs of quartz (amethyst) afterr calcite

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