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JOURNAL OF GLASS STUDIES
VOLUME 51 • 2009
Copyright © 2009 by The Corning Museum of Glass, Corning, NY 14830-2253
Alok K. Kanungo and Robert H. Brill
Kopia, India’s First Glassmaking Site:
Dating and Chemical Analysis
11
THE EARLIEST glass finds in India come
from Bhagwanpura in the northern state
of Haryana. They are dated to the period
of Painted Gray Ware (PGW) and the late Harap-
pan culture, about 1200 B.C.1 Later on, glass
is reported from almost all of the PGW sites
(about 1200–600 B.C.), but until now none of
the glass-yielding layers has been dated by radio-
metric techniques. Hence, our understanding of
the evolution of glassmaking in India and its
chronology has been uncertain and the dating
of specific finds has been, at best, only approx-
imate. Occasional references suggest that glass
imports—and possibly glassmaking technology
—were brought into southern India by well-
developed Indo-Roman trade in the first and sec-
ond centuries A.D., and that a glass industry was
established at Arikamedu on the Tamil Nadu
coast. From there, early glass products are pre-
sumed to have reached other parts of India.
This assumption is still held by many because
the history of glass in India has not been thor-
oughly re-examined since M. G. Dikshit’s land-
mark work, History of Indian Glass, was pub-
lished in 1969,2 despite the fact that much glass
has been discovered since that time.
More than 210 sites in India have provided
evidence of glass in different cultural horizons,
and 37 of them are claimed to be glassmaking
or glassworking sites.3 However, based on cur-
rent interpretations of the available data, the
dates of most of the glass-yielding sites are un-
convincing, as are the relationships of the glass
finds to the dated materials. Earlier archeolog-
ical investigations in India have focused on other
matters and neglected the dating. It is highly
like ly that from the Northern Black Polished
Ware (NBPW) period (about 600 B.C.) onward,
there were many regional centers of glass pro-
duction in India.
Recently, two glass beads dating to 1730 B.C.
(one from a stratigraphic context and the other
Kopia, India’s First Glassmaking Site:
Dating and Chemical Analysis
Alok K. Kanungo and Robert H. Brill
Acknowledgments. We are indebted to a number of scholars
for the excavation at Kopia and for obtaining the radiocarbon
dates. The late Dr. S. P. Gupta, director of the Centre for the
Study of History, Archaeology and Palaeoenvironment, New
Delhi, and Prof. V. N. Misra, former director of Deccan College,
were sources of constant encouragement and help. Dr. Rakesh
Tewari, director of the Uttar Pradesh State Archaeology Depart-
ment, Lucknow, extended all the logistical help for the excava-
tion. We are grateful to Prof. Peter Bellwood, secretary-general
of the Indo-Pacific Prehistory Association (IPPA), for making
the IPPA–Arizona dating scheme available. We also thank those
who provided the dating for the Kopia site: G. V. Ravi Prasad;
K. Dutta of the Institute of Physics AMS Facility, Bhubaneswar;
M. G. Yadava of the Radiocarbon Lab, Physical Research Lab-
oratory, Ahmedabad; and G. W. L. Hodgins of the NSF Arizona
AMS Facility, University of Arizona. A. K. Kanungo is grateful
for financial support provided by the 2005 Rakow Grant for
Glass Research from The Corning Museum of Glass, and he
thanks the staff of the museum for many helpful suggestions and
contributions. Shana Wilson assisted with the handling of our
analytical data and the plotting of the graphs.
1. Jagat Pati Joshi, Excavation at Bhagwanpura, 1975–76
and Other Explorations & Excavations, 1975–81 in Haryana,
Jammu & Kashmir, and Punjab, Memoirs of the Archaeological
Survey of India, no. 89, New Delhi: the survey, 1993, p. 117.
2. Moreshwar Gangadhar Dikshit, History of Indian Glass,
Bombay: University of Bombay, 1969.
3. Alok Kumar Kanungo, Glass Beads in Ancient India: An
Ethnoarchaeological Approach, British Archaeological Reports
International Series, no. 1242, Oxford: John and Erica Hedges
Ltd., 2004, pp. 88–91; idem, “Glass Beads in Ancient India and
Furnace-Wound Beads at Purdalpur: An Ethnoarchaeological
Approach,” Asian Perspectives (University of Hawaii Press), v.
43, no. 1, Spring 2004, pp. 123–150, esp. p. 123.
12
a surface find) were found at Harappa,4 and
seven were uncovered in a late Harappan buri-
al, reportedly of the second millennium B.C., at
Sanauli, Uttar Pradesh.5 One of the authors (A.
K. Kanungo) has documented eight glass beads
from Chalcolithic Balathal, dating to the mid-
third millennium B.C.6 However, none of the
beads from either site has been scientifically an-
alyzed, and those from Sanauli have not been
scientifically dated. (We note that, in the past, al-
though small finds have been identified as glass,
they have sometimes turned out to be faience or
other materials, or made from minerals.) Al-
though the beads at Balathal were found in a
Chalcolithic level, they could have intruded from
the overlying Early Historic deposit. This same
possibility applies to Ahar, where a few glass
beads were found in the Chalcolithic level but
the excavator believed that these could have mi-
grated from pits in Early Historic deposits.7
Against this background, excavations at Ko-
pia are being conducted with four objectives: (1)
to obtain precise dating for the manufacture of
the glass by radiometric methods, (2) to apply
that knowledge toward defining a more accurate
chronological framework for the general evolu-
tion of glass in India, (3) to learn more about the
origins of the Kopia glass, and (4) to investigate
the technology of glass manufacture at Kopia.
In addition, we hope eventually to shed light on
glassmaking relationships that probably existed
between the subcontinent and the Indus Valley
civilizations.
The Kopia Site
Kopia (26°52´ N, 83°4´45 ˝ E, Fig. 1), located
in the Sant Kabir Nagar district of Uttar Pra-
desh, extends over an area of about one square
kilometer, and it rises about 10 meters above
the surrounding ground level. On the basis of
surface finds, it was long believed to have been
a major glass manufacturing center of the fifth
century B.C.8 The site was well fortified and sur-
rounded by a moat. There is a substantial area
of occupation outside the fortification as well.
Most of the evidence of glass production was
found outside the fortification, toward the north-
ern end of the mound. This part of the deposit
is within 250 meters of the fortification, but it
is about seven meters lower than the fortified
area. Thus, it is possible that material from the
fortified area was also found in these outer de-
posits.
The Excavations
In three seasons of excavations at the site
(2004–2006),9 26 trenches, each of which mea-
sured five square meters, were excavated, either
fully or in quadrants, covering a total area of
418.75 square meters. Eight of these trenches
lay in the center of the mound, inside the forti-
fication, and three were located on the western
boundary of the fortification. Combined, they
are designated as Locality I. All of the remaining
4. Jonathan Mark Kenoyer, personal communication with
A. K. Kanungo.
5. Dharamvir V. Sharma, Kishan Chand Nauriyal, and Vel-
lore Nandagopal Prabhakar, “Excavations at Sanauli, 2005–06:
A Harappan Necropolis in the Upper Ganga-Yamuna Doab,”
Puratattva (New Delhi), v. 36, 2005–2006, pp. 166–179, esp.
p. 174.
6. Virendra Nath Misra, “Balathal: A Chalcolithic Settlement
in Mewar, Rajasthan, India: Results of First Three Seasons’ Ex-
cavation,” South Asian Studies (Cambridge University), v. 13,
1997, pp. 251–273.
7. Hasmukh Dhirajlal Sankalia, S. B. Deo, and Z. D. Ansari,
Excavations at Ahar (1961–62), Pune: Deccan College, 1969, p.
163.
8. A. Fuhrer, The Monumental Antiquities and Inscriptions
in the North-Western Provinces and Oudh, v. 2, New Delhi:
Archaeological Survey of India, 1891; P. Roy and Y. P. Varsh-
ney, “Ancient Kopia Glass,” The Glass Industry, v. 34, 1953,
pp. 366–392; Dikshit [note 2], p. 39; S. N. Sen and Mamata
Chaudhuri, Ancient Glass and India, New Delhi: Indian Na-
tional Science Academy, 1985, pp. 64–65; B. B. Lal, “Glass Tech-
nology in Early India,” in Archaeometry of Glass: Proceedings
of the Archaeometry Session of the XIVth International Con-
gress on Glass, ed. H. C. Bharadwaj, Calcutta: Indian Ceramic
Society, 1987, pp. 44–56, esp. p. 45; Abdugani A. Abdurazakov,
“Indian and Central Asian Connections: A Study Based on
Chemical Analyses of Glasses,” in ibid., pp. 37–43.
9. The results of these excavations are published in A. K. Ka-
nungo and V. N. Misra, “Excavation at Kopia: A Preliminary
Report,” Puratattva, v. 34, 2003–2004, pp. 116–126; A. K.
Kanungo and V. S. Shinde, “Excavation at Kopia 2005: A Pre-
liminary Report,” Puratattva, v. 35, 2004–2005, pp. 126–134;
and A. K. Kanungo, “Excavation at Kopia 2006: A Preliminary
Report,” Puratattva, v. 36, 2005–2006, pp. 103–111.
13
trenches were situated in Locality II, which lies
toward the north and outside the fortification.
On the basis of information from previous
surface exploration and initial trial trenches, the
central part of the mound was selected for ob-
taining the cultural sequence and information
about important structures. The northern slope
was selected for information about the work-
ing-class habitation, and the northwestern slope
was used for investigating the glass technology.
The Glass Finds and Glass Furnace
The finds from the excavation leave no doubt
that Kopia was a manufacturing center for glass,
and its entire economy appears to have been
based on glassmaking and glassworking. The
cul tural sequence revealed by the excavation
shows that the site was occupied from the Fine
Gray Ware (FGW; 700–600 B.C.) and NBPW
periods through the Mauryan (300 B.C.) and
FIG. 1. Map showing Kopia (center, unmarked) and immediate surroundings.
14
Sunga-Kushana (200 B.C.–A.D. 100) periods,
and into the Gupta period (about A.D. 400–
600). Although we have no firm dates for the
Gupta-period deposit, the cultural materials,
such as seals and terra-cotta figurines, give am-
ple evidence of a Gupta-period occupation. In
Locality I, glass is found in large quantities in
Mauryan levels, while excavation in the pre-
Mauryan NBPW level was limited to the index
trench. In the industrial area near the northern
end of the mound, the layer yielding glass and
evidence of its production—including the re-
mains of a glass furnace—is dated to the Sunga-
Kushana period (Fig. 2).
Innumerable pieces of glass, glass slag, tu-
yères, and crucible fragments with molten glass
attached were found in Trench AWX32, where
a furnace was exposed (Figs. 3–6). This is the
earliest glass furnace found in India, and it rais-
es several questions: What glass production
technology was used at Kopia? Were there any
furnaces earlier than this one? Where did the
raw materials come from? For whom was such
a large quantity of glass produced? Who con-
trolled its production? When and how did the
production technologies develop (i.e., were they
borrowed or indigenous)? What were Kopia’s
interactions with other settlements? These ques-
tions, although unanswered for the present,
will be explored further in the final excavation
report.
It is important to note that, throughout Lo-
cality I, the central part of the site, there is evi-
dence of burning and the destruction of struc-
tures between Layers 2 and 3. These could have
been caused either by accidental fire or by an
invasion. The height of the fortification seems
to have been raised after the burning. The char-
coal from the burning has been assigned a ra-
diocarbon date of 207 B.C. ± 189. Moreover,
there is a distinct cultural phase between the
NBPW and Sunga-Kushana periods, in the form
of a predominant red ware of the Mauryan pe-
riod.
Chronology
We have 20 accelerator mass spectrometry
(AMS) and radiocarbon dates for the site. The
detailed data will be included in our final report.
The dates were determined by three laborato-
ries: 10 by the Institute of Physics, Bhubanes-
war; seven by the Physical Research Laborato-
ry, Ah medabad; and three by the University of
FIG. 2. Remains of furnace in Locality II.
15
Arizona. The dates obtained by these three lab-
oratories are remarkably close—indeed, almost
identical—which testifies to the inherent reli-
ability of the AMS and radiocarbon methods.
All of the dates were obtained from charcoal
samples that came from seven trenches in all
parts of the mound. Three of these samples are
stratigraphically inconsistent and should be ig-
nored. The remaining 17 samples can be treated
as valid for the entire site. Six are from Sunga-
Kushana layers, six from Mauryan layers, and
five from NBPW layers.
The earliest date obtained, from Locality I, is
656 B.C. ± 134 (calibrated). It came from the
FIG. 3. Glass found with furnace.
FIG. 4. Broken tuyères found with furnace.
FIG. 5. Crucible pieces found in furnace.
FIG. 6. Reconstruction of crucible shown in Figure 5.
Haphazard grooves as
grips to hold clay coating
Thick clay coating to
resist high temperature
16
index trench, while the latest date, A.D. 153 ±
96 (calibrated), came from an adjacent trench.
In Locality II, the glassmaking area, the dates
are from only the lowest layer. These show the
beginning of the habitation in the northern and
northwestern ends of the mound at 1930 B.P. ±
70 and 2100 B.P. ± 90 (both uncalibrated) re-
spectively. The furnace is dated to 1960 B.P. ±
100.
Both the excavated finds and the radiocarbon
dates suggest that glass production in Locality II
started much later than the beginning of occu-
pa tion. It may be that glassmaking was intro-
duced during the Sunga-Kushana period, after
the burning and destruction of the site around
200 B.C.
The radiocarbon dating of the Kopia site, con-
sidered along with the nature of the glass finds,
begins to bring into focus a dating framework
that might be applied to other sites in India
where similar glass finds have been uncovered.
Thus, we might now be in a position to recon-
sider the chronology of glassmaking throughout
India.
Furthermore, the Kopia glass operations dem-
onstrate that India had mastered certain impor-
tant aspects of glassmaking even before there
was contact with Rome. Indo-Roman trade con-
tacts date to the first and second centuries A.D.
Kopia lay along the southern Silk Route, and
that part of India experienced little or no con-
tact with Rome. There is, in fact, little evidence
of early glass manufacturing elsewhere on that
part of the Silk Route—and as yet no evidence
of production on a scale comparable to that in
Kopia. There is no clear evidence for the making
of glass vessels at Arikamedu. For example, the
pillar-molded bowls found there arrived through
later trade. Glass at Kopia was made in the same
copper red, green, and blue colors that have been
excavated at other sites, but Kopia also produced
yellow, black, brown, light blue, orange, and
white glass, some in transparent shades. All of
FIG. 7. Drawn tubes for beads (?) in Locality II.
FIG. 8. Glass beads in Locality II.
17
the beads found at Arikamedu are of the drawn,
typically Indo-Pacific shape, while those uncov-
ered at Kopia include drawn, collared, and seg-
mented beads. In addition, several of them are
wound (Figs. 7 and 8). In addition, Kopia has
yielded a number of glass bangles in various col-
ors (Fig. 9) and a neck fragment of a bottle dat-
ing to the first century A.D. This makes the glass-
working at Kopia unique in India. The largest
chunk of glass found in India was also produced
at Kopia. It weighs 60 pounds, and it is now in
the Lucknow Museum.
Glass and glass beads from Arikamedu may
have played a role in sea trade, but as far as
overland and hinterland trading of glass artifacts
is concerned, it seems that Kopia, located on the
southern Silk Route, may have been an impor-
tant center for glass production and trade from
at least the third century B.C. onward.
Much of the previous research on glass found
in India concludes (solely on the basis of mor-
phology) that the glass had been brought in by
trade from Arikamedu. (For example, consider
the glass from Candraketugarh in Kolkata.10)
But now the excavation and radiocarbon dat-
ing of the glassmaking operations at Kopia raise
the need for reconsideration—and perhaps a re-
vision—of that simplistic point of view. Chem-
ical analyses shed further light not only on the
Kopia glasses but also on their relationships
with glass es excavated elsewhere in India. The
whole picture of Indian glass and glassmaking
has changed.
SCIENTIFIC INVESTIGATIONS
OF SOME GLASS FROM KOPIA
This report presents a summary of our find-
ings for a group of 16 samples of glass from
Kopia that were analyzed in 2006. Analyses of
samples from the excavations that followed are
under way. Brief sample descriptions are given
at the end of this report. Tables of the complete
data will be included in a future publication and
in A. K. Kanungo’s excavation report.
Sample nos.:
8420–25, 27–29, 31, 32, 34, 35, 37, 40, 41:
glasses (16)
9710, 11: riverine sands (2)
9754: described as reh, but primarily quartz
and other minerals (1)
FIG. 9. Glass bangles in Localities I and II.
10. Sharmi Chakraborty, “Candraketugarh: A Cultural and
Archaeological Study (500 B.C. to 500 A.D.),” Ph.D. diss.,
Deccan College, Pune, 2000.
18
Compositions:
I. 8421, 24, 25, 27–29, 31, 32, 34, 35, 37,
40, 41: Na2O:CaO:SiO2 (high Al2O3, low
CaO) (13 glasses).
II. 8420, 22, 23: K2O:SiO2 (three glasses).
Sands and reh (three samples).
Analyses performed:
Quantitative analyses by inductively coupled
plasma spectroscopy and semi-quantitative
analyses by emission spectrography, X-ray
diffraction of batch materials, and stron tium
isotope analyses of representative glasses.
Mean Compositions:
I. Soda-Limes (n=13) II. Potash-Silica (n=3)
90%
C.L.
Mean
90%
C.L.
Stand.
Dev.
R.D.
%
90%
C.L.
Mean
90%
C.L.
Stand.
Dev.
R.D.
%
SiO2*d 65.52 70.18 74.84 2.82 4.0 79.22 81.30 83.38 1.26 1.6
Na2O* 13.35 15.45 17.55 1.27 8.2 0.26 0.51 0.75 0.15 29.4
CaO* 1.47 2.78 4.10 0.80 28.8 1.74 2.19 2.63 0.27 12.3
K2O* 2.26 2.99 3.72 0.44 14.7 11.08 12.86 14.65 1.08 8.40
MgO* 0.85 1.56 2.27 0.43 27.6 0.31 0.40 0.49 0.06 15
Al2O3* 4.29 5.29 6.30 0.61 11.5 1.93 1.95 1.97 0.01 0.51
Fe2O3* 1.01 1.74 2.47 0.44 25.3 0.49 0.79 1.09 0.18 22.8
Al2O3
/SiO2 0.075
Two Riverine Sands from Near Kopia
CMG 9710 CMG 9711
SiO2 83.32 85.52
Na2O 0.73 1.16
CaO 0.28 0.64
K2O 2.11 1.87
MgO 0.73 0.65
Al2O3 8.36 7.39
Fe2O3 3.74 2.23
TiO2 0.49 0.30
Al2O3
/SiO2 0.100 0.0864
19
Discussion
The data for this group of samples produced
interesting and important findings. Two dis-
tinctly different families of chemical composi-
tions were found. The first contains 13 soda-
lime glasses having relatively low lime contents
(= or < about 4% CaO) and high alumina con-
tents (~ 4.5%–6.5% Al2O3). This is a family of
compositions that we recognize from our earlier
studies and that we associate with glasses found
in India.11
The other family is the potash-silica composi-
tion. We know that glasses of this type are found
throughout East Asia and Southeast Asia, and
as far west as India. We believe that such glass-
es may have been made at more than one loca-
tion within that region, and that beads and
bracelets in particular (but possibly also some
vessel glass) were widely traded there.12 Occa-
sionally, we have found potash-silica beads from
sites farther west, but we suspect that they were
imported from India. For example, our glass no.
5530, from Jenné-Jeno in Mali,13 has this type
of composition. Our no. 5522, from that same
site, could be a bead of the other Indian type,
the low-lime, high-alumina glass.
These two families of glasses, which typify
glass found—and probably made—in India,
match the mean values reported here for the Ko-
pia glasses, as well as the Kopia points plotted
in Figures 10–14. Four of the graphs are those
we routinely plot for soda-limes. In addition, we
have included a graph that clearly illustrates the
difference between the low-lime, high-alumina
Indian glass and Roman and Hellenistic natron-
based soda-limes (Fig. 11). The ellipse in that
graph encloses some examples of Indian glasses
from our 1987 publication.14 Although they are
not identical to the Kopia glasses, the deviations
may perhaps be explained by the fact that the
glasses came from different sites in India and
that they could be of different dates. Nonethe-
less, the two groups of data are consistent with
the existence of that Indian family of low-lime,
high-alumina soda-lime glasses. The alumina/
silica ratio for the Kopia soda-limes is about
2.50–2.75 times greater than for the more than
400 Roman and Hellenistic glasses in the graph.
These groups of glasses are distinctly different
from each other, and they must have been made
from different types of batch materials.
The other graphs also make it apparent that
there are differences—including some color dif-
ferences—among the Kopia glasses of the soda-
lime type. In addition, the samples may be of
somewhat different dates.
It has become apparent that, in general, an-
cient black glasses (which normally are actually
very dark amber) frequently contain unusually
high levels of alumina and iron. The most fa-
miliar examples of these glasses are bangles and
bracelets found in India,15 in Southeast Asia, and
occasionally in the West at places such as Sar-
dis.16 We wonder if the glasses with such high
alumina may have been colored with iron slags
—or, possibly, if obsidian was used as a source
of silica.
One of the graphs shows the correlation of
iron and alumina. Since the straight line of this
11. Robert H. Brill, “Chemical Analyses of Some Early In-
dian Glasses,” in Archaeometry of Glass [note 8], pp. 1–25.
12. Robert H. Brill, “Scientific Investigations of Ancient
Asian Glass,” in UNESCO Maritime Route of Silk Roads. Re-
port, Nara Symposium ’91, Nara, Japan: The Nara Interna-
tional Foundation, 1993, pp. 70–79; idem, “Scientific Research
in Early Asian Glass,” Proceedings of the XVIIth International
Congress on Glass, v. 1, Invited Lectures, Beijing: Chinese Ce-
ramic Society, 1995, pp. 270–279; R. H. Brill, P. M. Fenn, and
D. E. Lange, “Chemical Analyses of Some Asian Glasses,” ibid.,
v. 6, pp. 463–468; Robert H. Brill, “Opening Remarks and Set-
ting the Stage,” in Study on Ancient Glass along the Silk Road,
ed. Gan Fuxi and Robert H. Brill, Shanghai: Fudan Press, 2008,
pp. 30–47; Robert H. Brill and Hiroshi Shirahata, “The Second
Kazuo Yamasaki TC-17 Lecture on Asian Glass: Recent Lead-
Isotope Analyses of Some Asian Glasses,” in Study on Ancient
Glass along the Silk Road, in press; Robert H. Brill, Chemical
Analyses of Early Glasses, Corning: The Corning Mu seum of
Glass, 1999, v. 1, Catalogue of Samples, pp. 150–176, and v. 2,
Tables of Analyses, pp. 358–362 and 364–367.
13. R. H. Brill, “Chemical Analysis of Some Glasses from
Jenné-Jeno,” in Excavations at Jenné-Jeno, Hambarketolo, and
Kaniana (Inland Niger Delta, Mali): The 1981 Season, ed. S. K.
McIntosh, Berkeley: University of California Press, 1994, chap.
5, pp. 252–256, and fig. 38.
14. Brill [note 11].
15. Ibid.
16. Brill, Chemical Analyses [note 12], v. 1, p. 67, and v. 2,
p. 110.
20
FIG. 10. Lime vs. soda for Kopia glasses.
FIG. 11. Alumina vs. lime for Kopia glasses compared
with Roman and Hellenistic glasses.
% Na2O*
0
0
1
2
3
4
5
5 10 15 20
% CaO*
Kopia glasses (n=16)
° = Soda-lime (13)
• = Potash-silica (3)
Ellipse indicates nine glasses
from other sites in India.
Kopia01.stg
AKopia.sta
% CaO*
0 1 2 3 94 105 116 127 13
% Al2O3*
0
1
2
3
4
5
6
7
8
8 14
SupRHK67.stg
SupRHKop.sta
Kopia soda-lime glasses
compared with Roman and
Hellenistic natron-based glasses
• = Kopia (n=13)
° = Roman (n=384)
+ = Hellenistic (n=47)
Ellipse indicates nine glasses
from other sites in India.
21
FIG. 12. Magnesia vs. potash for Kopia glasses.
FIG. 13. Alumina vs. silica for Kopia glasses.
% K2O*
0
0
1
2
3
4
5 10 15
% MgO*
Kopia02.stg
AKopia.sta Kopia glasses (n=16)
° = Soda-lime (13)
• = Potash-silica (3)
Ellipse indicates nine glasses
from other sites in India.
Kopia glasses (n=16)
° = Soda-lime (13)
• = Potash-silica (3)
Ellipse indicates nine glasses
from other sites in India.
% Al2O3*
0
1
2
3
4
5
6
7
8
60 65 70 75 80 85 90
% SiO2*
Kopia03.stg
AKopia.sta
22
plot passes through the origin, it appears that
all of the iron in these glasses was introduced
with the ingredient that introduced the alumi-
na—which is not surprising if one assumes that
the ingredient that introduced the alumina into
the Indian soda-limes was the same as that used
for making the potash-silica glasses. Presuma-
bly, that ingredient would have been a sand. Of
course, this may be coincidental, but it is worth
remembering as one explores further the possi-
bility of relationships between these two families
of glasses.
The three potash-silica glasses from Kopia are
similar to potash-silica glasses from elsewhere
in India in that most of them contain slightly
greater levels of lime than some glasses in the
same family excavated in Southeast Asia and
East Asia. The latter contain slightly less than, or
slightly more than, 1.0% CaO. While we regard
the potash-silica glasses as a single chemical fam-
ily, we do see it as a broad chemical type, and
we believe that there are distinctions among the
individual glasses that are related to the use of
somewhat different sources of local batch in-
gredients or to differences in dates of manufac-
ture.
Two samples of sands (perhaps they should
be called sandy soils) were collected by A. K.
Kanungo from riverbanks near the site of his
excavation. They are CMG nos. 9710 and 9711.
Their major and minor components are listed
on page 18. The alumina/silica ratios for these
two sands average about 0.093, as compared
with 0.075 for the 13 Kopia soda-lime glasses.
Thus the glasses are somewhat “cleaner” in alu-
mina than the sands. Nevertheless, the alumina
in the sands comes close to accounting for the
high alumina contents of the glasses.
The results of the analysis of the sample of reh
were disappointing in that the sample proved to
be primarily silica, as established by both chem-
ical analysis and X-ray diffraction. The diffrac-
tion work, performed by Erika Stapleton of Cor-
ning Incorporated, showed that the predom inant
phase by far was alpha-quartz, although minor
phases of bernalite, lepidolite, and mica were
FIG. 14. Iron vs. alumina for Kopia glasses.
% Fe2O3*
0
1
2
3
4
0 1 2 3 4 5 6 7 8
% Al2O3*
Kopia glasses (n=16)
° = Soda-lime (13)
• = Potash-silica (3)
Ellipse indicates nine glasses
from other sites in India.
% Fe2O3* = 0.025 + 0.33* (% Al2O3*)
Kopia04.stg
AKopia.sta
23
also present. Only a minor amount of thermo-
natrite (a form of hydrated sodium carbonate)
was found. Hence, we conclude that the sample
was more contaminated with soil than the other
samples of reh and of oos that we had analyzed
previously.17
The histogram (Fig. 15) shows strontium iso-
tope ratios measured for 271 samples of glasses,
Egyptian blues, Chinese purples, and probable
batch materials.18 These analyses were performed
by Prof. Paul D. Fullagar of the University of
North Carolina.
All of the materials from India—including
13 glasses, three minerals, and a crucible shard
from Kopia—have high strontium isotope ratios
that are entirely different from those character-
izing glasses from more westerly sources and
from East Asia. This offers further evidence for
the existence of an “Indian family” of glass com-
positions. It is also consistent with the likelihood
that those glasses (including all but one of the
Ko pia soda-limes) were made in India. The high
87Sr /
86Sr ratios are not only different from those
of “Western” glasses, but the Indian glasses and
minerals also conform to the high values ex-
pected for minerals from that part of Uttar Pra-
desh.
The histogram shows that the data for about
130 Egyptian, Mesopotamian, Hellenistic, Ro-
man, and Islamic glasses (and related materials)
fall at the far left side of the graph. The glasses
are all natron-based or plant-ash soda-limes.
They are enclosed well inside the first two bars,
along with medieval European stained glass win-
dows. (The stained glass windows lie mainly in
the second bar from the left and are thereby dis-
tinguishable from the soda-limes.)
Twelve of the soda-limes from Kopia form a
tightly coherent isotopic group having high ra-
tios. Only one glass from Kopia lies within the
17. Ibid., v. 1, p. 212, and v. 2, p. 481.
18. Robert H. Brill and Paul D. Fullagar, “Strontium-Isotope
Analyses of Some Historical Glasses and Related Materials: A
Progress Report,” Annales de l’Association Internationale pour
l’Histoire du Verre, v. 17, Antwerp, 2006 (in press).
FIG. 15. Histogram showing distribution of strontium isotope ratios
for various types of glasses.
No. of Objects
0
20
40
60
80
100
120
140
160
180
200
220
0.69 0.7 0.72 0.73 0.74 0.75 0.76 0.77 0.780.71
87 Sr /
86 Sr
“Western” glasses
(Egyptian, Roman, Islamic, etc.)
Stained glasses
India a
(2)
*
Kopia a
8422
Kopia b
(12)
India b
(4)
India sands
(2)
SrHist1c.stg
*
24
“Western” glasses bar and thus may be consid-
ered an import—but not one from the West be-
cause it is one of the three potash-silica glasses
from Kopia. On the basis of the strontium iso-
tope value of this single sample, one would con-
clude that the potash-silica glasses recovered
from the glass furnace site were not produced
locally. However, that requires further consider-
ation. Among the two dozen potash-silica glass-
es for which we have strontium isotope data,
only one other piece has such a low ratio: no.
6421, a large bracelet with a triangular cross
sec tion, from Lang Vac in Vietnam.
I (R. H. Brill) am very pleased by the pros-
pect of continuing our collaboration with Dr.
Kanungo on this extremely important glass site
in India.
SAMPLE DESCRIPTIONS
2005 Excavation, Fortified Area
8420. Small, flat fragment with curved edge.
Aqua. Crizzled surface. Level 12, reg. no. 513.
8421. Flattened circular “counter”(?). Light
green, turbid. Lightly weathered. Level 4, reg.
no. 375.
8422. Section of bangle, flattened cross sec-
tion. Transparent light blue, with reddish sur-
face in places. Little or no weathering. Level 5,
reg. no. 387.
8423. Bead fragment, indefinite shape. Light
green, turbid. Lightly weathered. Level 11, reg.
no. 493.
8424. Section of bangle, half-round cross
section (d. ~ 6 cm). Black. Little or no weath-
ering. Level 6/7, reg. no. 558.
8427. Bottle rim with top of neck (?). O.D.
6 cm. Green. Lightly weathered. Level 2, reg.
no. 51.
8429. Small nugget of cullet. Brownish
amber. Little or no weathering. Level 3/4, reg.
no. 546.
8430. Small nugget of cullet with refractory
adhering. Green, turbid. Little weathering.
Level 1, reg. no. 286.
2005 Excavation, Glass Area
8431. Section of large bangle, rounded tri-
angular cross section. Black. Little weathering,
but matte surface. I.D. 4 cm, Alt. 7 mm, W.
(base) 9 mm. Level 1/2, reg. no. 571.
2004 Excavation, Fortified Area
8432. Small barrel-shaped bead. D. 6 mm,
L. 1.5 mm. Opaque light green. Lightly weath-
ered. Level 1, reg. no. 29.
8433. Section of bangle. I.D. 7 cm. Blue,
turbid; very seedy. Little or no weathering.
Level 1, reg. no. 145.
8434. Section of bangle. I.D. 6 cm. Yellow-
ish(?) green; very seedy. Little or no weather-
ing. Level 1, reg. no. 117.
8435. Section of bangle. I.D. 7 cm. Black
(very dark amber). Little or no weathering.
Level 1, reg. no. 18.
8436. Section of bangle, chipped and
possibly deformed by fire. Black. Little or no
weathering. Level 1, reg. no. 122.
8437. Section of bangle, flat cross section.
I.D. 7.5 cm. Black. Little or no weathering.
Level 2, reg. no. 176.
8438. Small piece of cane or bangle. Light
blue, turbid. Light to moderate weathering.
Level 2, reg. no. 176.
8439. Small piece of cullet. Pale green, with
patch of refractory attached. Lightly weathered.
Reg. no. 46.
2004 Excavation, Glass Area
8425. Tube with bore and slight bulge, many
drawn-out bubbles. Nearly colorless. Little or
no weathering. Level 3, reg. no. 131.
8426. Tube with bore and knot, many
drawn-out bubbles. Black. Little weathering.
Level 1, reg. no. 109.
8428. Nugget of cullet. Green, slightly tur-
bid, with few patches of red material fused onto
surface. Little weathering. Level 1, reg. no. 193.
25
8440. Fragment of cylindrical bead. D. 1.0
cm. Colorless. Lightly weathered. Level 1, reg.
no. 149.
8441. Bead, roughly cylindrical, with small,
thin, narrowed tip. D. 9.5 mm, L. 1.6 mm (ex-
cluding drawn tip), widest perforation 4 mm.
Pale greenish aqua, turbid. Lightly weathered.
Level 1, reg. no. 153.
8442. Small, thin, narrow tube. Light blue,
turbid. Lightly weathered. Level 1, reg. no. 150.
8443. Bead waster. Small cylindrical piece
attached to smaller hollow bead. Apparently
formed from one tube that did not separate.
Pale yellowish aqua. Lightly weathered. Level
3, reg. no. 148.
8444. Small lump of slaglike waste consisting
of bubbly green glass fused to refractory mate-
rial or soil. Level 2, reg. no. 209.
8445. Glass removed from folded rim (or
edge?) of crucible. Surface find, but dated to
the first or second century A.D. Terra-cotta
fabric is soft and has a more or less uniform
brownish red color throughout. Fragment
arrived broken in mail (March 18, 2006), but
its dimensions must have been ~ 6.5 cm along
curved rim x ~ 5.1 cm in width x ~ 3.5 cm
maximum thickness. Wall thickness ~ 4–6 mm
throughout. Apparent curvature of original
vessel ~ 28 cm. Four radial mold marks or
decoration located near edge. Glass fills the
otherwise hollow space inside the folded terra-
cotta. Sample is of very pale greenish glass.
Little or no weathering, but heavy internal
shattering.
8446. As above, sample of body of crucible,
brownish red coarse ware.
