Dear Mr. Zemri:

As an economic geologist and mineralogist dealing with fluorite, I do not fully understand the aim of your investigations. I provide you with information on some papers of mine which might be of help to you (?) and which you can download from the RG server:

DILL, H.G. and WEBER, B. (2010) Accessory minerals of fluorite and their implication concerning the environment of formation (Nabburg-Wölsendorf fluorite district, SE Germany) - With special reference to fetid fluorite (“Stinkspat”).- Ore Geology Reviews 37: 65-86.

DILL, H.G. and WEBER, B. (2010) Variation of color, structure and morphology of fluorite and the origin of the hydrothermal F-Ba deposits at Nabburg-Wölsendorf, SE Germany.- Neues Jahrbuch für Mineralogie Abhandlungen, 187: 113-132.

DILL, H.G., HANSEN, B.T. and WEBER, B. (2011) REE contents, REE minerals and Sm/ Nd isotopes of granite- and unconformity-related fluorite mineralization at the western edge of the Bohemian Massif: with special reference to the Nabburg-Wölsendorf District, SE Germany.- Ore Geology Reviews, 40: 132-148.

DILL, H.G., WEBER, B., EIGLER, G. and  KAUFHOLD, S. (2012) The fluorite deposits NE of Regensburg, SE Germany-A mineralogical and chemical comparison of unconformity- related fluorite vein-type deposits.- Geochemistry 72: 261-278.

DILL, H.G.,  LUNA, I., NOLTE, N. and  HANSEN, B. T. (2016) Chemical, isotopic and mineralogical characteristics of volcanogenic epithermal fluorite deposits on the Permo-Mesozoic foreland of the Andean volcanic arc in Patagonia (Argentina).- Geochemistry  76: 275-297.

I hope it will be of assistance to you.

Best regards

H.G.Dill

Dear Professor H.G.Dill,

First of all, I am very thankful to the time and concerns that you showed to my question, also all my gratitude for the documents toward which you oriented me,

Well, I am sorry for the lack of explication, I will try to explain what is going on in my mind in words:

we are conducting a metallogenic study for the fluorite ore deposit in morocco, in this aim we used (REE analyses, C/O isotopes, Sr Isotopes, Pb/ S isotopes, Noble Gazes, and Fluid inclusions), and those days I found that there is a method used  to reconstruct the compositions of  REY   of fluorite if it was precipitate from a granitic magma using a theory called ( Lattice-strain), in fact,  Van Hinsberg (2010) states that the trace element partitioning between minerals and aqueous fluids is systematic and obeys lattice-strain theory. It depends strongly on element complexation in the fluid, but this dependence is predictable and can be accommodated. Unlike fluids, minerals with preserved compositions are readily available in the geological record, and the "lattice-strain" approach

therefore provides a powerful and widely applicable tool to reconstruct a quantitative record of fluid composition for the full range of Earth environments and for its earliest history. (end of quote).

Well, this Idea crossed my mind after that i found that an other PhD student ( that I can't get in thouch with) used it in his final presentation to get his PhD dissertation, I will add a figure to this text, to make it more clear,

I Hope that I was able to explain my thoughts,

best regards,

Oussama ZEMRI

P.S: the references cited:

van Hinsberg, V. J., Migdisov, A. A., & Williams-Jones, A. E. (2010). Reading the mineral record of fluid composition from element partitioning. Geology, 38(9), 847-850.