Dear Pouria Salami,

The following text was taken from a publication entitled "The Geology of Rare Earth Elements " by Keith R. Long et al. which describes the sources and geographical sites where rare earth elements can be found (USA) and the different mineral processing.

Mineral Processing for Challenges

The ores of rare earth elements are mineralogically and chemically complex and commonly radioactive.

In many base and precious metal deposits, the metals extracted are highly concentrated in a single mineral phase, such as copper in chalcopyrite (CuFeS2) or zinc in sphalerite (ZnS). Separation of a single mineral phase from rock is a relatively easy task. The final product is a concentrate typically sent to a smelter for final extraction and refining of the metals. Zinc, for example, is almost entirely derived from the mineral sphalerite, such that the global zinc smelting and refining industry has developed a highly specialized treatment of this mineral. Thus, production of zinc has a pronounced cost advantage in that a single standard technology is used, and the development of a new zinc mine is a largely conventional process.

Current mineral-processing practice is capable of sequential separation of multiple mineral phases but it is not always cost effective to do so. When elements of interest are found in two or more mineral phases, each requiring a different extraction technology, mineral processing is relatively costly. Many rare earth elements deposits contain two or more rare earth elements-bearing phases. Therefore, rare earth elements deposits in which the rare earth elements are largely concentrated in a single mineral phase have a competitive advantage. To date, REE production has largely come from single-mineral-phase deposits, such as Bayan Obo (bastnasite), Mountain Pass (bastnasite), and heavy-mineral placers (monazite).

Complex Mineral Processing

Rare earth elements-bearing minerals, once separated, contain as many as 14 individual rare earth elements (lanthanides and yttrium) that must be further separated and refined. The complexity of extracting and refining rare earth elements is illustrated by a metallurgical flow sheet for the Mountain Pass mine in California (fig. 2). Unlike metal sulfides, which are chemically simple compounds, REE-bearing minerals are quite complex. Base metal sulfide ores, such as sphalerite (ZnS), are typically smelted to burn off sulfur and separate impurities from the molten metal. The resulting metal is further refined to near purity by electrolysis. Rare earth elements, on the other hand, are typically extracted and refined through dozens of chemical processes to separate the different rare earth elements and remove impurities.

The principal deleterious impurity in REE-bearing minerals is thorium, which imparts an unwanted radioactivity to the ores. Because radioactive materials are difficult to mine and handle safely, they are heavily regulated. When a radioactive waste product is produced, special disposal methods must be used. The cost of handling and disposing of radioactive material is a serious impediment to the economic extraction of the more radioactive REE-rich minerals, in particular monazite, which typically contains considerable amounts of thorium. In fact, imposition of tighter regulations on the use of radioactive minerals drove many sources of monazite out of the rare earth elements market during the 1980s.

The complex metallurgy of rare earth elements is compounded by the fact that no two REE ores are truly alike. As a result, there is no standard process for extracting the REE-bearing minerals and refining them into marketable rare earth compounds. To develop a new rare earth elements mine, the ores must be extensively tested by using a variety of known extraction methods and a unique sequence of optimized processing steps. Compared with a new zinc mine, process development for rare earth elements costs substantially more time and money.

To view the full publication, please use the following link:

http://geology.com/usgs/ree-geology/

In addition, you may be interested to read about rare earth elements in China which is described in the following link:

http://www.nature.com/articles/srep01776

Further, British scientists invoked new method to find copper deposits which is described in the following link:

 http://www.mining.com/uk-scientists-develop-new-method-to-find-copper-deposits/

Other links which may be of interest are:

https://encrypted.google.com/search?newwindow=1&q=related:pubs.usgs.gov/sir/2010/5220/downloads/SIR10-5220.pdf+new+method+for+checking+Iron+and+REE+deposits&tbo=1&sa=X&ved=0ahUKEwjV3M3Frt_MAhWIxRQKHZqECFEQHwg-MAQ

https://encrypted.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0ahUKEwjV3M3Frt_MAhWIxRQKHZqECFEQIAhHMAU&url=https%3A%2F%2Fwebcache.googleusercontent.com%2Fsearch%3Fq%3Dcache%3A_vU1_pPurtEJ%3Ahttps%3A%2F%2Fpubs.usgs.gov%2Fbul%2F1082b%2Freport.pdf%2B%26cd%3D6%26hl%3Den%26ct%3Dclnk&usg=AFQjCNFyHsAUHfPsvJQjaBAgKVRXEVdtEQ&sig2=TUEXYxE3Y1CbsOnNdi3hOg

https://encrypted.google.com/search?newwindow=1&q=related:https://www.bgs.ac.uk/downloads/start.cfm%3Fid%3D1638+new+method+for+checking+Iron+and+REE+deposits&tbo=1&sa=X&ved=0ahUKEwjV3M3Frt_MAhWIxRQKHZqECFEQHwhNMAY

The following link is a study on iron from central Iran

Extraction of iron alterations from ASTER SWIR and ETM+ data from Esfordi 1:100000 sheet (Central Iran)

ABSTRACT

Satellite images with the electro-magnetic spectrum range widely have been used in geology and mineral exploration. In this regard, geology structures of study area, lithology and alteration types can be considered as the most important extractable layers from the satellite images. Esfordi 1:100000 sheet is located in Central Iran structural zone, consists of Bafq iron ore district. There are many known iron ores in this sheet, such as Chadormalu, Choghart, Seh-Chahoon, Mishdowan, Zaghia and North anomaly. The aim of this research is processing the ETM+ and ASTER satellite images and extracted alterations associated with iron ores, for identification of new prospects. For this purpose, alteration zones associated with iron mineralization (hematite, limonite, jarosite and goethite) were extracted by some methods, e.g. Band Ratio (2/1 and 3/1), Visual Interpretation (RGB: 531,741, 742 and 754), PCA (Principal Component Analysis) and ARI. The PCA method in comparison with the other methods did not provide a good result. However, these methods were compared and their common areas were proposed as prospects, where the North to North-East, Central and North Western areas were introduced that by field checking they would confirm conclusively. Keywords: Remote sensing, Esfordi, Iron, Band Ratio, PCA, ARI.

*

https://www.academia.edu/22327647/Extraction_of_iron_alterations_from_ASTER_SWIR_and_ETM_data_from_Esfordi_1_100000_sheet_Central_Iran_

Hoping this will be helpful,

Rafik

Dear Pouria, 

As I worked on the same subject about a year ago, I prefer to share my stuff with you.

but please let me know what do you mean of " new methods"?

Just for the start, here I attach some papers which exactly concentrates on what you're interested in.

here are the titles > (all papers are in Persian)

1. ژئوشیمی عناصر خاکی کمیاب در کانسارهای اکسید آهن-آپاتیت منطقه معدنی بافق

فرهاد محمدتراب

http://www.gs-journal.ir/Files/1/Content/1.pdf

2.  زمین شناسی، کانی شناسی و ارزیابی اقتصادی عناصر خاکی کمیاب در پلاسر مروست، یزد

مسعود علی‌پوراصل

http://www.gs-journal.ir/Files/1/Content/2.pdf

3. پرعیارسازی نمونه پلاسری مونازیت مروست و استحصال عناصر نادر خاکی از کنسانتره محسن محمدخانی، غلامرضا ملاطاهری و احمد امینی

http://www.gs-journal.ir/Files/1/Content/3.pdf

http://www.gs-journal.ir/Files/1/Content/1.pdf

http://www.gs-journal.ir/Files/1/Content/2.pdf

http://www.gs-journal.ir/Files/1/Content/3.pdf

Dear Rafik

Thank you for your respond, I try to use all of your recommendation.

Best regard.

Dear Hossein

I want to work there for Msc thesis. 

Actually I want to know isotopic data for that area, is it suitable?

Thank you for your article.

Best wishes.

Do you mean the study of rock geochemistry using isotopic data of REEs or their economical study?

As it's not my field of research, you may want to get familiar with an expert. I know some expert researchers of this field.

But before that, please let me know about your goal.

thnx.

Dear Hossein

I want o know about isotopic data of REEs and economic of REEs.

My thesis is about Ore-prospecting and geochemistry of Iron Ore and related REEs in Chah Gaz mine and I want to use fluid inclusion and isotopic data in this thesis.

Best Wishes.

Very well, sound's good about the topic.

As I being informed, Chah Gaz mine contains a significant amount of apatite in its ore body. and REEs are in apatite crystals.

You may want to take a look at the Ph.D thesis of Farhad Mohammad Torab (my PhD thesis supervisor) or even contact him.

The title is > 

"Geochemistry and metallogeny of magnetite-apatite deposits of the Bafq Mining District,Central Iran"

you can have a pdf copy from here >

https://www.deutsche-digitale-bibliothek.de/binary/KMJ5266PH72USGVGP672RFHX3SSQM3GB/full/1.pdf

Also, it might be useful > "GEOCHEMISTRY AND RADIOISOTOPE STUDIES TO DETERMINE SOURCE OF APATITE IN THE BAFQ IRON-APATITE DEPOSITS"

written by Dr. Torab.

You can download a copy from here > 

http://www.ijcm.ir/articlefile/9-35-46-953-7-561-mahammad%20torab.doc

Beside, I found these papers >

In situ Sr isotope analysis of apatite by LA-MC-ICPMS: constraints on the evolution of ore fluids of the Yinachang Fe-Cu-REE deposit, Southwest China

and

کانی‌سازی و مطالعات سیالات درگیر کانسار اکسید آهن- آپاتیت خانلق، شمال شرقی ایران

Last two papers exactly targeted your field of interest.

http://webcache.googleusercontent.com/search?q=cache:http://aag.scu.ac.ir/article_11825_0.html

http://link.springer.com/article/10.1007%2Fs00126-015-0578-z

Here I add two more papers. The newer publication introducing new methods in your field of interest and the older one gives you some useful basic information about the topic.

Dear Hossein

Thank you for your kindness. I hope one day compensate your kindness.

Best wishes.

Pouria

you're welcome.

feel free to ask, and have a nice trip to ChahGaz.