Ph.D., Thesis presentation: Chemical Analysis of Archeological Pottery Excavated in Saudi Arabia, May 2018,

1. Chemical Analysis of
Some Archeological
Objects Excavated in
Saudi Arabia
A thesis submitted
By
Awad N Albalwi
PhD chemistry, science
Guided By
Prf. Ahmad H Al-Gamdi
Prf. Omar A Al-Dayel
Dr. Saud A Al-Gamdi

2. Outline
❑INTRODUCTION
❑CONCLUSION
❑OBJECTIVES
❑ METHODS
❑RESULTS & DISCUSSION

3. Project Objectives
• To determine the types and amounts of chemical components found
in archaeological materials uncovered in the ancient town of Dedan.
• To determine the number of ancient pottery categories using
elemental fingerprint patterns.
• To perform a provenance study of archaeological pottery objects .
• To classify ancient northwestern Arabian ceramics by applying
various statistical multivariate analysis of the data.
• To fill a gap in the field of chemical method application in the analysis
of the archaeological samples discovered in the Dedan excavation
site by establishing a chemical data site.
• To employ the afforded chemical data to extract some cultural
knowledge related to the ancient societies of the Arabian Peninsula.
• The research detailed in this thesis was designed to establish
whether it is possible to identify the most powerful elemental
fingerprint that can be used to separate studied ancient pottery
samples.

4. Ancient towns and trad routs
• The geographical position of the Arabian Peninsula between the ancient civilisations
of India and Persia and the states of eastern Mediterranean and Egypt, contributed
towards it becoming an important centre of trade and commerce.

6. pottery shards
The pottery shards exhibit numerous characteristics (including diversities in colour,
thickness, hardness, tempering material, vessel form, and decorative treatment) that
are highly useful to establish the general period of the site where they were found

7. Methodology

8. Results and Discussions
Elemental fingerprinting of ancient pottery using multivariate statistics
10% of Data for classification
36 potteries
30 elements

9. Principal Component Analysis (PCA)
PCA suggests four main ancient pottery groups
A PCA loading plot indicates the relationship between variables (elements) in the space of
the first two components. Elements that are correlated will be grouped together and have
arrows pointing in similar directions. Moreover, the greater the length of the arrow, the
stronger the influence the element has on the separation of the groups in the score plot
PCA scatter plot, (1) Abbasid/Islami, (2) Nabataean, (3)Tayma/Madyan, and (4) Dedan

10. Hierarchical Cluster Analysis (CA)
Dendrogram using Ward’s method and square Euclidean distance for 36 pottery samples: It is a techniques used to classify
cases into groups that are relatively homogeneous within themselves and heterogeneous between each other, on the basis
of a defined set of variables.

11. k-mean cluster analysis

12. 3D Scatterplots
3D scatterplots of 36 pottery shards from the Dedan site, the Abbasid/Islami (❏), ‘Dedan
(◊), Nabataean (❍), and Tayma/Madyan (∆) pottery samples.

13. Comparison of the mean elemental compositions

14. Stepwise discriminant analysis (SWDA)
SWDA was performed on the data to identify the best
classifying elements
SWDA identified Ni Zn Ga Rb Sr Cs Tl Li Sc, Zr V Cr
Th Tb Mn and Co as the most significant chemical
discriminators between the four compositional
groupings , derived two discriminant functions that
between them accounted for 100% of the variance
Label Wilks'
Lambda
Pr <
Lambda
Rb 0.1398 <0.0001
Ga 0.0250 <0.0001
Sc 0.0036 <0.0001
Zr 0.0007 <0.0001
V 0.0003 <0.0001
Sr 0.0001 <0.0001
Li 0.0001 <0.0001
Mn 0.00007 <0.0001
Ni 0.00005 <0.0001
Cs 0.00004 <0.0001
Zn 0.00005 <0.0001
Cr 0.00003 <0.0001
Th 0.00003 <0.0001
Co 0.00002 <0.0001
Tb 0.00001 <0.0001
Tl 0.00001 <0.0001
SWDA

15. Canonical discriminant analysis (CDA)
SWDA identified Ni Zn Ga Rb Sr Cs Tl Li Sc, Zr V Cr Th Tb Mn and Co as the most
significant chemical discriminators between the four compositional groupings , derived
Three discriminant functions that between them accounted for 100% of the variance
between the groups. This technique also confirmed that 100% of the sherds were correctly
classified

16. Provenance Study of Archaeological Pottery from
Dedan (The Sixth Season Excavation (2009)
The results for each ceramic class were compared with a local reference to distinguish
products from (Dedan) from those that were imported
• 126 pottery
• 24 clay
• Dedan
• Islami
• Nabataean
• Tayma/
• PCA
• CA
• SWDA
• CAN
• 2D/3D plot
• Box plot
• Marix
• Ternary
Determination of the provenance of pottery found during the excavation of a site can be
of great value in providing information on contacts between that site and others

17. Principal Component Analysis (PCA)
(0) Clay, (1) Abbasid, (3) Tayma, (4) Nabataean, and (6) Dedan.

18. 3D scatterplot and scatterplot matrix

19. 3D scatterplot and scatterplot matrix

20. Canonical discriminant analysis (CDA)
the variables that contributed most to the discriminant model were
Rb, Pb, Sc, Dy, Th, Ba, U, Ti, Lu, La, Yb, Ce, Mn, Ni, Co, Cr, Zn, and V

21. Investigating the similarity of the elemental composition of Dedan
pottery fragments from various excavation seasons

22. Discrimination Analysis
327 pottery sherds based on the 10 suggested groups
•
the SWDA identified Li, Be, Sc, Ti, V, Cr, Ga, Rb, Sr, Y, Zr, Ba, La, Ce, Tl, Th, and U (out of 29 variables)

23. Conclusion
• Classification of pottery: The results of 29 element concentrations
treated statistically by PCA, FA, CA, SWDA, CDA and k-mean clustering
suggested that pottery shards could be clustered into four well-
separated groups
• Provenance of pottery: One of the crucial results of this study was
the strong geochemical similarity between the Dedan ceramics and
the clay (geological) samples collected from al-Ula.
• One of the objectives of this work was to establish a data site of
chemical properties of ancient pottery excavated from the Dedan
heritage site, an important ancient town situated on the main old
trade route of the Arabian Peninsula and geochemical characteristics
of the al-Ula and Mada’in Saleh.
• This data site is documented in Index A and illustrates >16,000
figures of average concentration for 39 elements in about 420
samples

24. Suggestions
• Applying various of statistical patterns such as partial least squares
(PLS), k-nearest Neighbour (k-NN) method, Artificial Neural Networks
(ANN) are helpful for interpreting the data in new ways.
• More samples Madyan /Tayma pottery shards and clay samples need
to be analysed and compared to the results established in this study,
• More pottery samples from the historical town of Mabayat; the
investigated Islami/Abbasid pottery shards are believed to be similar
or originating from this area.
• Because of the large number of uncovered fragments from the Dedan
period, a study including pottery shards from every stratigraphy is
recommended; the afforded results should be compared to the
findings in this work.
• Chronological dating is needed to interpret the scattering of the
Dedan pottery shards. For instance, thermoluminescence dating (TL)
can be applied on selected samples from every identified group.

25. Recommendation
• Suggestion to establish the field of archaeological chemistry in the
Kingdom of Saudi Arabia:
• The Archaeological Research Laboratories is capable to employ a variety of
methods with a wide focus including biological, chemical, geological, and
physical analysis methods, which are applied to the archaeological remains.
• enamel, bone, hair, textiles, coins, pigments, water, soil, organic samples
can be prepared and analyzed using chemical and physical , thermal ,
biogeochemical techniques to answer anthropological questions.

26. Publishing

27. Acknowledgments
Prof. Dr. Hicham
Al-Nachawati
Prof. Dr. Ahmad
Hamed Al-Ghamdi
Examination
committee
Prof. Dr. Hassan Al-Swaidan
Prof. Dr. Abdulrahman Al-warthan
Dr. Mohamed Rahmtalla
You
All
Dr. Saud Abdulaziz
Al-Gamdi
Prof. Dr. Omar
Abdulrahman Al-
Dayel

28. Thank you all

29. acid digestion
• 360 pottery
• 60 clay
• 8 mL HNO3
• 2 mL HCL
• 2 mL HF
• Rh internal St
• 39 elements
• Ref material
• Sample Blank

30. Sample preparation for pottery fragments
I. Scrubbing to remove surface contamination.
II. Grinding to fine powder.
III. Drying 105 °C overnight .
Sample preparation (extraction)
Sample preparation for Clay
I. Grinding to fine powder.
II. Firing at 850 °C overnight.

31. statistical analyses
More than 100 pages
More than 16000
Element concentration

32. Samples Selection Criteria
Sampling Design
following sub-criteria to select the pottery shards:
1- Archaeological parameters (space, layer, and unit).
2- Manufacture places/type (local/Tayma:
Madyan/Islamic pottery/Greek/ Nabataean).
3- Pottery shard colors
4- Manufacturing quality
5- Raw material (clay/stone/sand/mixture and colors
of these materials).
6- Pottery forms (handle/base/part of the
body/edge)

33. Multivariate analysis
• principal component analysis (PCA)
• clustering analysis (CA)
• k-mean cluster analysis
• Stepwise discriminant analysis (SWDA)
• Canonical discriminant analysis (CDA)
• 2D and 3D scatterplot
• Matrix scatterplot
• Box plot
• Comparison of the mean elemental
compositions
• Ternary plot