FMF - Friends of Minerals Forum, discussion and message board

[Philip Simmons]

Hi all,

I posted this message on Mindat several days ago. I've already had some reponses about several different localities, but I think that there are many other localities outside of the US that people on the FMF forum are more familiar with.

I'm currently in the process of writing an article for one of the major mineral collecting magazines on evaporite minerals from New Mexico, and I need some help on other notable evaporite occurences around the world. I'm interested in Blue/Purple Halite, Sylvite, Langbeinite and Aphthitalite. Any information would be helpful, and I'm particularly interested in size of crystals, color, transparency, etc. for these four minerals. Most people are at least familiar with halite and sylvite, but because aphthitalite and langbeinite are much more rare, the worldwide information on these two minerals is quite lacking. I've already done a lot of research on the web including Mindat, FMF and Webmineral, but I know that there are limitations on the knowledge of these lesser know minerals posted on the web. I have looked at the Best Mineral pages on Mindat, and while the information is useful, it is by no means complete or thoroughly comprehensive. I'm curious to find out what kind of information is unearthed from such a broad base of mineral collectors around the world.

I greatly appreciate any information offered! It doesn't make a difference whether you post on this thread or send me a PM.

Regards,
Philip Simmons

[cascaillou]

The french mineralogical journal 'mineraux et fossiles' published three special issue volumes titled 'Les mineraux leurs gisements, leurs associations' by Pierre Bariand, Fabien Cesbron and Jacques Geffroy. In the second volume (special issue number 21) there is some general information about the mineral Aphthitalite (K,Na)3Na(SO4)2 formerly named glaserite.
Compiled data includes habit/morphology (with drwing of a tabular crystal), colors, physical and optical properties, different geological settings for the specy, known localities of occurence, best crystals (with size and locality).

These special-issue volumes provide more exhaustive data for other evaporites (including halite, sylvite and a few others...), but I could't find any information about Langbeinite.

I'm not going to copy the all text, but if you want me to report on some specific information from these books, just tell me what you need exactly, and for which evaporite minerals.

Here's a quote about Aphthitalite geological settings:

from fumaroles (Vesuve and Etna in Italia, Kilauea in Hawai islands) and also as evaporites of salty lakes such as Searles (California). It is also found in saline deposits: Stassfurt (germany), Carlsbad (new-mexico), Kalusz (Ukraine). The nicer crystals, 1 to 2cm in size and setted on halite, are from Kuh-E-Namak dome which is nearby Ghom in Iran.

[cascaillou]

By the way, here's another interesting ressource for minerals:
https://handbookofmineralogy.com
(link normalized by FMF)

go to search handbook PDFs 'by first letter'

You will find Aphthitalite and Langbeinite data in there (including largest reported crystal size range, but it is not told in which geological setting these larger crystals specifically occured)

[Philip Simmons]

cascaillou,

Thank you very much for the information and website. In my previous research I had found the Mineralogy Handbook PDF, I just wasn't sure where the information had come from. The pages on aphthitalite and langbeinite I was already using for for the basis of the section on each respective mineral. Now I know where the information comes from.

Was the information you quoted about aphthitalite from the French Mineralogical Journal volume number 2? If so, the specimens that have been recovered recently from New Mexico for both aphthitalite (~15 cm) and langbeinite (~10 cm) are possibly the largest ever found.

I find it interesting that you should mention Pierre Bariand because I was directed to contact him by somebody from Mindat as well. I have some contact information, so hopefully I can contact him and find out more specific information on these minerals.

Again, thank you very much for your helpful information!

Best Regards,
Philip Simmons

[Miguel Calvo]

[cascaillou]

Philip, yes the text I quoted is from the french mineralogical journal.
However I'm not sure what they mean by 'The nicer crystals, 1 to 2cm in size'.
Possibly this claim is a misconception or is just outdated, but maybe 'nicer' doesn't necessarly mean biggest, it's possibly a reference of overall quality of the specimens.

There are quite a few evaporite minerals (some of which can occur in different geological settings), are you planning to cover these all in your paper?

I remember as a kid I had a colorful piece of sylvite, I guess I had licked it quite a few times because I can still remember exactly how it tastes.

[cascaillou]

Note that there are a few books about evaporites specifically

[Philip Simmons]

Miguel,

Where can I find your book? I assume the book is in Spanish only? My high school Spanish is pretty rusty, but I should be able to work through the text slowly.

Thanks,
Philip

[Philip Simmons]

cascaillou,

Do you know when the special volumes of the french mineralogical journal were published? It seems to me that from the Journal information you gave me, the best quality specimens of apthitalite crystals were 1-2 cm. I imagine that larger crystals were found, but they just were not of very good quality. The 15 cm crystal I mentioned in a previous post was extracted in many small pieces, but several complete crystals up to 9 cm were found that were of the best quality.

The purpose of the article I'm writing is to specifically cover the minerals found in the Carlsbad Potash District, New Mexico. I will also include some information on other noteworthy localities worldwide.

The minerals I am focusing on are Blue/Purple Halite, Sylvite, Aphthitalite (glaserite), Langbeinite, Carnallite, Leonite, Gypsum, Kainite, Keiserite and Polyhalite.

I can understand why you still remember tasting the sylvite when you were a kid! Every time I have to differentiate between halite and sylvite (taste is the easiest method of identification), the sylvite seems to give me a kick in the mouth!

Best Regards,
Philip