LAB REPORT ON XRF OF POTTERY SAMPLES By BIJOY KRISHNA HALDER Mohammad Arif Ishtiaque Shuvo Jie Hong

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1 LAB REPORT ON XRF OF POTTERY SAMPLES By BIJOY KRISHNA HALDER Mohammad Arif Ishtiaque Shuvo Jie Hong

2 Introduction: X-ray fluorescence (XRF) spectrometer is an x-ray instrument used for routine, relatively non-destructive chemical analyses. XRF is the emission of characteristic "secondary electron" (or fluorescent). It works on wavelength dispersive spectroscopic principles which are similar to electron microprobe (EPMA).However, XRF isn t used to analyze at the small spot sizes typical of EPMA work (2-5 µ), so it is typically used for bulk analysis of larger fractions of geological materials. The relative ease and low cost of sample preparation, and the stability and ease of use of x-ray spectrometers make this one of the most widely used methods for analysis of major and trace elements in rock, mineral, sediments and articraft. Physics of XRF: X-rays from a material that has been excited by bombarding with high-energy X- rays. Ionization of the component atoms may take place when materials are exposed to short-wavelength X-rays or to gamma rays. Ionization consists of the ejection of one or more electrons from the atom, and may occur if the atom is exposed to radiation with energy greater than its ionization potential. The characteristic x-rays are labeled as K, L, M or N to denote the shells they originated from. Another designation alpha (α), beta (β) or gamma (γ) is made to mark the x-rays that originated from the transitions of electrons from higher shells. Hence, a Kα x-ray is produced from a transition of an electron from the L to the K shell, and a Kβ x-ray is produced from a transition of an electron from the M to a K shell, etc. Since within the shells there are multiple orbits of higher and lower binding energy electrons, a further designation is made as α1, α2 or β1, β2, etc. to denote transitions of electrons from these orbits into the same lower shell. Initially the process of XRF initiates when an X-ray photon of sufficient energy strikes an atom, it dislodges an electron from one of its inner shells (K in this case) (Step 1). And then the atom fills the vacant K shell with an electron from the L shell; as the electron drops to the lower energy state, excess energy is released as a K a X-ray (Step 2a), at last the atom fills the vacant K shell with an electron from

3 the M shell; as the electron drops to the lower energy state, excess energy ener is released as a KβX-ray (Step 2b). Step 1 Step 2b Step 2a 2 ray fluorescence, in a schematic representation. Fig 1: Physics of X-ray Instrumentation: X-ray ray fluorescence gun. The For the elemental analysis we have used a portable X model name is X-MET MET 300TXV+. Fig 2: X-MET 300TXV+

Material and Methodology: We have analyzed four samples

These samples are labeled as Sample A: 17153 (M); Sample

Sample A Sample B Sample C Sample D This lightweight,

4 Material and Methodology: We have analyzed four samples with that instrument. These samples are labeled as Sample A: (M); Sample B: (P); Sample C: (A) and Sample D: (E). Sample A Sample B Sample C Sample D This lightweight, handheld XRF analyzer can create X-ray for the sample analysis by running at 40 kv and 7 ma. It was run for 300s to provide the spectrum for each element. Then a software PyMCA is used to analyze these spectrums data.

5 Data and Result: After calibrating and analyzing with PyMCA software, all the plots each sample is given below: and tables for Sample A: 17153[M] Data plot for sample 17153[M] in log scale Element Group Area Fit Area Sigma Area fraction Element Group Area Fit Area Sigma Area fraction P K 1.62E E E-04 Rb K 8.85E E E-02 Cl K 2.67E E E-04 Sr K 1.72E E E-01 K K 1.40E E E-02 Y K 5.30E E E-02 Ca K 1.18E E E-01 Zr K 1.77E E E-01 Ti K 2.09E E E-02 Nb K 5.40E E E-02 V K 2.81E E E-03 Mo K 4.79E E E-02 Cr K 4.58E E E-03 Pd L 6.79E E E-04 Mn K 3.40E E E-03 Ag L 3.52E E E-04 Fe K 6.85E E E-01 Cd L 1.55E E E-04 Co K 2.18E E E-02 Sn L 1.45E E E-03 Ni K 1.07E E E-03 Sb L 2.75E E E-02 Cu K 5.65E E E-03 Te L 8.33E E E-03 Zn K 2.08E E E-02 W L 7.60E E E-04 Ga K 1.78E E E-03 Pt L 3.37E E E-03 As K 4.61E E E-03 Au L 8.41E E E-02 Rb K 9.19E E E-03 Bi L 1.04E E E-02 Se K 9.19E E E-03 Rn L 2.26E E E-02 Br K 7.63E E E-03 Ac L 5.58E E E-02

6 Sample B: 17153[P] Data plot for sample 17153[P] in log scale Element Group Fit Area Sigma S K 7.65E E+01 Cl K 4.31E E+01 K K 1.52E E+01 Ca K 8.70E E+02 Ti K 2.35E E+01 V K 2.66E E+01 Cr K 3.66E E+01 Mn K 1.85E E+01 Fe K 9.10E E+02 Co K 2.73E E+01 Ni K 3.13E E+01 Cu K 4.43E E+01 Zn K 2.25E E+01 Ga K 2.11E E+01 As K 8.06E E+01 Se K 1.01E E+01 Br K 7.11E E+01 Fraction Element Group Fit Area E-04 Rb K 6.70E E-04 Sr K 2.21E E-03 Y K 5.45E E-02 Zr K 1.79E E-02 Zr L 3.53E E-03 Nb K 6.36E E-03 Mo K 5.89E E-04 Ag L 2.21E E-01 Sn L 3.44E E-02 Sb L 2.03E E-04 Te L 2.42E E-03 W L 3.68E E-02 Pt L 3.62E E-03 Au L 8.29E E-03 Bi L 9.51E E-03 Rn L 2.21E E-03 Ac L 6.52E+03 Sigma Fraction 1.14E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E E-02

7 Sample C: 21022[A] Data plot for sample 21022[A] in log scale Element Group Fit Area Sigma Element Group Fit Area Sigma Fraction Fraction S K E E E-04 Sr K E E E-01 Cl K E E E-04 Y K E E E-02 K K E E E-03 Nb K E E E-02 Ca K E E E-03 Mo K E E E-02 Ti K E E E-02 Pd L E E E-04 V K E E E-03 Ag L E E E-03 Mn K E E E-04 Cd L E E E-04 Fe K E E E-01 Sn L E E E-03 Co K E E E-02 Sb L E E E-03 Ni K E E E-04 Te L E E E-04 Cu K E E E-03 W L E E E-04 Zn K E E E-02 Pt L E E E-03 Ga K E E E-03 Au L E E E-02 As K E E E-03 Pb L E E E-03 Se K E E E-03 Bi L E E E-03 Br K E E E-03 Rn L E E E-03 Rb K E E E-02 Ac L E E E-02

8 Sample D: 21022[E] Data plot for sample 21022[E] in log scale Element Group Fit Area Sigma P K 1.94E E+01 S K 1.25E E+01 Cl K 1.19E E+01 K K 1.92E E+01 Ca K 2.09E E+01 Ti K 3.02E E+01 V K 2.41E E+01 Cr K 4.37E E+01 Mn K 4.82E E+01 Fe K 8.34E E+02 Co K 2.45E E+01 Ni K 6.21E E+01 Cu K 4.85E E+01 Zn K 3.24E E+01 Ga K 2.64E E+01 As K 9.58E E+01 Se K 8.67E E+01 Br K 1.02E E+01 Rb K 8.01E E+02 Fraction Element Group Fit Area 9.62E E-04 Sr K 2.72E E-04 Y K 5.99E E-03 Zr K 2.58E E-02 Nb K 7.02E E-02 Nb L 1.81E E-03 Mo K 6.80E E-03 Pd L 5.31E E-03 Ag L 6.08E E-01 Cd L 6.71E E-02 Sn L 6.76E E-04 Sb L 2.39E E-03 Te L 1.14E E-02 W L 3.09E E-03 Pt L 3.15E E-03 Au L 8.55E E-03 Bi L 9.77E E-03 Rn L 1.75E E-02 Ac L 6.61E+03 Sigma 1.93E E E E E E E E E E E E E E E E E E+02 Fraction 1.35E E E E E E E E E E E E E E E E E E-02

9 In the above tables the fit area is the count of each element. However, the fit area does not give the amount of respective element present in the sample. And mass fraction provides the proportion of each element in the sample. After that the elements for highest counts were taken and compared with four samples. The highest counts common in four samples are Fe, Au, Sr, Rb. Two elements were taken at a time for comparison from all four samples. Here, Sample A (M), Sample B (P), Sample C (A) Sample D (E) is blue diamond, red square, green triangle and cross purple respectively.

10 1.20E+05 Rb Vs Fe 1.00E+05 Fe 8.00E E E E+04 Sample A Sample B Sample C Sample C 0.00E E E E E E E+04 Rb

12 From above comparison, it is clear that except Rb vs Fe and Rb vs Sr which shows the nature of same origin, but for all other plots the points are scattered. At last mass fraction for element with highest count as well as highest mass fraction is plotted in column graph. Title: Fraction of elements per sample

13 From above column graph it is evident that Fe is the main element in each sample we analyzed. Interestingly Au and Rb are almost similar for samples (P), (A) and (E). It is observed that for above each four elements in the sample (A), (E) the mass fraction values are very close to each others. Conclusion: From the data and plot obtained, we can recapitulate that as most of the elemental comparison graphs showed scattered points, all the samples are not from similar source. And the most abundant elements in the samples are Iron, Gold, Stronsium and Rubidium.

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1 of 5 14/10/ :21 X-ray absorption s, characteristic X-ray lines... 4.2.1 Home About Table of Contents Advanced Search Copyright Feedback Privacy You are here: Chapter: 4 Atomic and nuclear physics Section: 4.2 Absorption