Elemental analysis of Kimberlite and associated Country Rock

Elemental analysis of Kimberlite and associated Country Rock Marius Tchonang 1, Martin Cook 1, Faan Bornman 2 Simon Connell 1 and Sergio Ballestrero 1 1 Physics Department, University of Johannesburg 2 Multotec Process Equipment (Pty) Ltd

Outline Context (Min. PET) Experiment Analysis Results and Conclusion

Context (Min. PET) coarse crush gamma beam irradiatio n hopper planar PET detector hold hopper (20 min) ejection flaps

Experiment (Aarhus University) Kimberlite The 100 Me. V electron Microtron The gamma spectrometer

The composition of Kimberlite (wt% major, ppm trace elements) Grey Kimberlite Altered Grey Kimberlite Black Kimberlite Si. O 2 43. 5 39. 1 40. 96 Ti. O 2 0. 74 0. 83 2. 21 Al 2 O 3 3. 66 3. 77 2. 87 Fe 2 O 3 4. 90 4. 05 5. 03 Fe. O 2. 70 2. 89 4. 28 Mn. O 0. 16 0. 25 0. 10 Mg. O 27. 85 36. 0 27. 25 Ca. O 3. 64 0. 42 6. 02 Na 2 O 0. 20 <0. 1 0. 71 K 2 O 0. 67 0. 20 1. 22 H 2 O+ 8. 20 9. 89 7. 47 H 2 O- 0. 91 1. 89 1. 10 P 2 O 5 0. 13 0. 19 CO 2 0. 20 0. 22 0. 15 Total 97. 5 99. 4 99. 6 Ni 1354 950 1338 Cr 728 752 1370 Sr 139 79 n. d.

Analysis (Time differential gamma-ray Spectroscopy) 845. 8 ke. V Calibrated energy spectrum with the dominance of the 511 ke. V PET line Time differential gamma spectroscopy for life-time determination for each gamma-line

Analysis Continued

Analysis Continued

Analysis Continued Area under the fit gives new data which are a function of the peak height Single spectrum for the 845. 8 ke. V gamma-line for consecutive time slices

Analysis Continued Single decay fit gives T 1/2=62 min Single decay fit of the 845. 8 ke. V peak

Analysis Continued

Analysis Continued T 1/2=10 min for the unknown species Two species fit with one fixed to 56 Mn

Analysis Continued

Analysis Continued Sum of 56 Mn and 27 Mg fit of the 845. 8 ke. V peak

Analysis Continued Sum of 11 C, 13 N and 15 O fit of the 511 ke. V peak

51 1 ke V Results 27 Mg 56 Mn (9. 46 min) (2. 58 h) 24 Na (15 h) 52 Mn 40 K (21 min) (Years) Double escape from 2754 ke. V Single escape from 2754 ke. V 24 Na (15 h)

Acknowledgement u I would like to thank the University of Johannesburg for the financial support u All the members of the psi group THANK YOU