Yes. There are some ways. You can check the HSC software which is released by OTUKOMPU company, and select , Mineralogy section which will be helpful in this case. Also you can calculate by some formulas. I attached an excel document which is mostly about mineralogy proportions in copper porphyry ore. Hope to be useful. 

Dear Ahmad,

Thank you very much for your kind answer and consideration. You will appreciate very much if you have a copy from the HSC software to send me a copy, if possible. The spreadsheet you kindly sent is not so clear. I do not know how to use the bulk-rock analysis of any igneous rocks to calculate the mineral proportions.

Thanks again for your help.

Dear Dr. Ahmed,

your question can hardly be responded to with a simple answer. There have always been attempts to obtain the mineralogical composition without taking a look at the mineralogy under the ore or petrographic microscope, or using any other more highly-sophisticated method such as EMPA. The classical examples of calculating the modal composition in igneous petrology you may find in each good textbook on petrography. If you have a simple Pb-Zn-Cu ore with galena, sphalerite and chalcopyrite it may be simple to get an answer. The same is true for calcareous rocks. And last-but-not least it depends upon your goal; is it for applied or for genetic economic geology. I would like to raise a strong error warning, as you might persuade yourself to be on the true side and totally go into the wrong direction if you trust too much in a software. I recommend prior to the use of software programs converting the chemical composition into a mineralogical one to carry out a good petrographic and/or mineralogical study. The risk of being mislead is too big, especially when dealing with issues in the genetic part of economic geology, where even small and more exotic minerals count.

I wish you all the best.

Harald G. Dill

Dear Dr. Dill,

Thank you very much for your kind answer and considerations. You are totally right, especially when we are dealing with the evaluation of economic mineral deposits, no way than the microscopic study. In my case I am studying the petrology of mantle rocks, juts would like to know the tentative mineral proportions in the rocks without the routine counting process, although it is the more accurate one. I can roughly estimate the mineral distributions, but I think it will be more precise if there is a way to estimate that from the whole rock analysis, I think.

Anyway, thanks again for your message and cautions. 

Dear Ahmed,

I would suggest you to estimate the modal mineralogy with a preliminary petrographical study, and then use the composition of minerals obtained by EPMA if available. If you have a bulk-composition and EPMA data, then, you would just need to use an excel spreadsheet to change the preliminarily estimated modal mineralogy to catch the obtained whole rock composition. And, please test this first with point count methods before applying this method to your samples.

Good luck,

Ibrahim

Ahmed,

The CIPW Norm calculation is designed to approximate the mineralogy of normal igneous rocks based on their bulk chemical composition.  Your "mantle rocks" should fit this criteria unless they are unusual.  Details of the calculations, as well as the limitations of there use, are outlined in most introductory igneous petrology textbooks.

Dear Ahmed

It 's very easy to calculate the CIPW Norm by using the Minpet application. You can download it free in the internet. It's also fast method. Good luck

Thank you all, Ibrahim, Thomas and Hassan, for your kind suggestions and help. I will use CIPW norm, of course after petrographic observations, to characterize the mineral proportions.

Thanks again for your kind considerations.

Ahmed

CIPW norm is the best way to know hypothetical mineral compositions compatible to the particular whole-rock analyses, however, there is no way to know the actual mineral  compositions of the rocks from whole-rock analyses

Thanks Saumitra for your message. No problem for the mineral composition, already done by EPMA. Just I was asking about mineral proportion from whole rock analysis. Thanks again for all.

Ahmed

Hi,

Determinbation of modal mineralogical abundant is difficult and not reliable from the whole rock geochemical anaylsis. In my opinion, you must examine your rocks with polarizan microscope. That is best way. Cheers.

To do a modal mineralogy calculation based on whole rock chemistry, there are to many options where specific chemical elements can go. Never the less you could do a normative calculation. It is at the end a idealized mineralogy of the rock, but usually it comes close to the real mineralogy. To understand the process check out Kurt Hollochers Website and he also  developed a Excel spreadsheet. http://minerva.union.edu/hollochk/c_petrology/norms.htm

to do modal mineralogy,rittman norm or CIPW norm or by polarizen microscobe

From bulk rock analysis you may get a kind of pseudo-mineral classification by using various norm calculations, as CIPW, acronym known from the fathers of this method, three petrologists Cross, Iddings and Pirrson and a geochemist, Whashington. A useful sofware is IGPET. I think you may get it for free.

Try linear algebra. If you have analytical data of your minerals you should obtain results quite consistent with the real percentages by weight, which are then convertible  to vol%.

The basics of the linear algebraic methods may be found in: Thompson AB, Rubie DC (eds) ... Ferry JM (1982) Linear algebraic manipulation of n-dimensional composition space....

The mostly used, by calculating the CIPW norm. 

Whole rock data by themselves can not give a singular solution to mineral modes. However, if you have xrd or other qualitative estimates of mineral modes, you can get reasonable quantitative estimates from LPNORM (Caritat et al 1994). Copies of LPNORM can be obtained from Patrice de Caritat at Geoscience Australia. 

There is an Excel program named MINSQ of Herrmann and Berry (2002) that using an iterative method with the whole rock analysis and mineral composition of rock-forming minerals (determined by microprobe for example) you can get the mineral proportion in a more reliable method than CIPW norm as you are considering real mineral compositions.  I have used quite a lot and works very well. The paper that explain the use of the program was published in Geochemistry: Exploration, Environment, Analyys, vol 2, 361-368. In the paper you can obtain the place where download the program.

I hope it helps you.

Javier

Dear Javier,

Thank you very much for your kind answer and help. If you do not mind, kindly send me the excel spreadsheet and the article, since the publications of this journal is not available for me online.

Thanks in advance.

Regards,

Ahmed

I haven't got both of them here in the office. As soon as possible I send you the program and the paper.

Javier 

Thanks Javier for your help. I could find both the article and excel sheet in the internet and already downloaded them. If you are interested, and any of the colleagues, it is attached herein. But I feel that the spreadsheet is not satisfied for me since many of the rock-forming minerals are not present (e.g. olivine, orthopyroxene, clinopyroxene, amphibole ...), so I could not depends on this program to characterize the mafic-ultramafic rocks. 

best regards.

Ahmed

Dear Ahmed,

If you use CIPW norm,  (see W. Cox, Interpretation of Igneous Rocks) and you will find how to allocate all those minerals.

Best regards,

Z Silva

You can use IGPET program that can be downloaded free. It is very easy to use, you have also a manual.

Regards,

Ioan

You can use the attached program

Have not been using this for a long time, so I can't be helpful. Sorry.

Thanks for asking this question Mr. Ahmed. Such problems occur when we attempt trace element modelling with a starting material whose modal mineralogy is unknown and all we know is the bulk composition. Choosing CIPW NORM or iterative modal mineralogy from bulk composition seems only way although such processes have their own limitations.

I'm looking for the CIPW that inlcude hydrous phases ! can anyone help me on this ?

thank you

You can use the GCDkit software for normative calculations (no modal % of minerals). You can download it free. It works under the R program and you can use an excel file. It is very easy to use.

Good luck

Yes. It is possible with the help of PETROG hardware and supportive software.

Yes sir, you can calculate normative mineralogy from bulk (Major oxides) rock chemistry with the help of the MS-Excel Norm sheet. This sheet is freely available on internet.

Hi,

You can use a norm-calculation to advise. You can download this from my website (useful spreadsheets): www.geoplotters.com

Alternatively, you could try putting your data through Melts software. Easy Melts has a very friendly graphical interface now.

Good old fashioned thin sections are best.