33rd Philippine Chemistry Congress May 30 to June 1, 2018

1. CHEMICAL CHARACTERIZATION
AND SOCIOCULTURAL IDENTITY
OF HISTORICAL POTTERY FROM
PILA, LAGUNA, PHILIPPINES
De La Salle University, Manila
33rd Philippine Chemistry Congress
May 30 to June 1, 2018
Aniano N. Asor Jr.
Bubbles Beverly N. Asor
Jan-Michael C. Cayme

2. Outline of presentation
I. Research Aims
II. Overview
III. Research insights
- Cultural heritage of pottery
- Sociocultural identity of pottery
III. Context and Method
IV. Data and results
V. Conclusion

3. I. Research Aims
• To categorize chemical characterization as one
of the dimensions of sociocultural identity of
pottery
• To characterize the Pila pottery from Laguna
and determine its chemical components

4. I. Overview: Cultural heritage

5. II. Cultural Heritage of Pottery
• Pottery tends to be reserved for pots, dishes and other
functional items while ceramics are fine art pottery
that describes artistic works (Violatti, 2014)
• Ceramic analysis answers complex questions about
economy, subsistence, technological innovation,
social organization, and data (Holmquist, 2017; Hunt,
2017)

6. II. Sociocultural Identity of Pottery
• Identification is constructed on recognition of common
origin or shared characteristics with another person or
group with natural closure of solidarity and allegiance
(Hall, 1996).
• People used pottery for constructing their social identity,
or showing who they were and how they were different
from other people (Carr, 2018)
• 3 dimensions: technology, durability, social visualization

7. Technology Durability
Social
Visualization
Chemical
Characterization
Pottery

8. III. Context and Method
• Why Pila, Laguna?
Laguna de Bay is a trading route for Chinese
merchants during pre-Spanish period.
• Method/s
- Secondary data analysis
- Chemical characterization

9. Flowchart
samples from potsherd
FT-IR XRF AAS

10. III. Chemical Characterization
• Collection of Pottery
• Analysis by Fourier Transform Infrared
Spectroscopy (FT-IR)
• Analysis by X-ray Fluorescence (XRF)
• Atomic Absorption Spectroscopy (AAS) of lead
(Pb)

11. Sample PPL1

12. Sample PPL2

13. Sample PPL3

14. IV. Data and Results
• Historical Profiling of
Pila Pottery
• Laguna de Bay as
trading route
• Esso-Elizalde Project
(1967)

15. IV. Technology as a Dimension of
Pottery
• Techniques, skills and methods in production
• Thermal shock, tensile strength and crack
propagation
• Types of clay and tempering materials
• Sculpturing, modeling and decoration types
• Porosity, flexural strength, linear shrinkage
and water absorption

16. IV. Durability as a Dimension of
Pottery
• Glaze chemistry and firing temperature
• Relationship of oxide chemistry and fired
durability
• Plenty of Al2O3 and SiO2

17. IV. Social Visualization as a Dimension
of Pottery
• Cultural traditions and social practices
regulate, expresses and transform human psych
• Survey, modeling, prototyping and interactive
visualization
• Pottery associated with social, economic and
symbolic practices

18. IV. Chemical Characterization
as a ‘new’ Dimension of
Pottery

19. ANALYSIS by FT-IR
Sample PPL1
18
23
28
33
38
43
400900140019002400290034003900
Wavenumber (cm-)
%T
3446
O-H
2924
C-H
1441
C-O
1637
H-O-H
1085
Al-Si-O
792
Si-O
646
Al-O-Si
584
Fe-O
2362
Si-O

20. ANALYSIS by FT-IR
Sample PPL2
15
17
19
21
23
25
27
29
31
33
35
400900140019002400290034003900
Wavenumber (cm-1)
% T
3450
O-H
2926
C-H
1441
C-O
1635
H-O-H
1084
Al-Si-O
793
Si-O
642
Al-O-Si
582
Fe-O
2362
Si-O

21. ANALYSIS by FT-IR
Sample PPL3
0
5
10
15
20
25
400900140019002400290034003900
Wavenumber (cm-1)
% T 3442
O-H
2931
C-H
1421
C-O
1637
H-O-H
1084
Al-Si-O
796
Si-O
648
Al-O-Si
573
Fe-O
2366
Si-O

22. FT-IR absorption bands in wave number (cm-1 ) with
relative intensities
sample PPL1 sample PPL2 sample PPL3 vibrational assignment
3446 3450 3442 O-H str. of adsorbed
water
2924 2926 2931 C-H str. of organic
contaminants
1441 1441 1421 C-O str. of calcite
1637 1635 1637 H-O-H bending of
adsorbed water
1085 1084 1084 Al-Si-O str. of
amorphous
aluminosilicate
1045 1051 1051 Si-O str. of clay
minerals

23. FT-IR absorption bands in wave number (cm-1) with relative
intensities
sample PPL1 sample PPL2 sample PPL3 vibrational
assignments
792 793 796 Si-O symmetrical
str. of quartz
646 642 648 Al-O-Si str. of
feldspar
584 582 573 Fe-O bend of
magnetite
530 530 532 Fe-O bend of
hematite
464 467 461 Si-O-Si bending of
silicates

24. ANALYSIS by XRF
Elements present Sample PPL1 Sample PPL2 Sample PPL3
Silicon (Si) 18.67 % 23.46 % 23.77 %
Aluminum (Al) 9.14 % 11.82 % 11.31 %
Calcium (Ca) 7.06 % 1.78 % 5.54 %
Iron (Fe) 2.76 % 6.23 % 1.83 %
Potassium (K) 1.45 % 8530 ppm 1.86 %
Light Elements 57.67 % 54.25 % 53.21 %
Manganese (Mn) 9430 ppm 880 ppm 1.00 %
Titanium (Ti) 3340 ppm 6220 ppm 3830 ppm
Sulfur (S) 8720 ppm 270 ppm 910 ppm
Phosporus (P) 9430 ppm 7290 ppm 7470 ppm
Zinc (Zn) 514 ppm 477 ppm 1393 ppm

25. V. Conclusion
• Chemical characterization can be another dimension to
deepen and enrich the understanding of the sources of
sociocultural identity of pottery in the Philippines
• Chemical characterization has a wider scope in
determining the source of pottery compared to the other
3 dimensions
• Confirmatory result and analysis of FT-IR and XRF

26. Acknowledgements
• Chemistry Department, De La Salle University
Dr. Jaime Raul Janairo, Chair
Mr. Michael Ajero, Dr. Carmen Tan, Mr. Irving Chiong
• Nympha Pajarillaga, Cytek Solutions, Inc
(www.cytekgroup.com)
• Mr Enrique Cruz, Baranggay Pinagbayanan property
site cutodian
• Ms Teresita Reyes, property caretaker
• Pinagbayanan Barangagay Captain Ruben Albayda