Chapter 8: Agate Acquisition Networks | Download PDF
New Introductory Paragraph by Randall Law, 2024
Although Harappans used a bewildering range of agates (translucent microcrystalline silicates) to
fashion beads and other ornaments, they seem to have favored the reddish-orange variety that is
commonly known as carnelian. In this chapter, agate-carnelian artifacts from Harapa are compared to
samples from sources in India and Iran using Instrumental Neutron Activation Analysis.
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AGATE ACQUISITION NETWORKS
Chapter introduction – Sourcing Harappan agate
The roughly 4700 finished objects (mostly ornaments but also the occasional stone weight) and pieces of raw material or manufacturing debris from Harappa that have been designated agate or jasper exhibit a bewildering range of macroscopic variability (recall Figure 4.3 C for just a handful of examples). Although HARP co-director Dr. J. Mark Kenoyer has developed an intricate coding system for describing such variation, visual attributes alone cannot be used to identify their geologic sources. As was the case for steatite, multiple macroscopic types of agate and jasper are usually found at source locations (personal observations) and, in fact, often are present in individual specimens (note, for instance, the variegated appearance of some of the agate samples pictured in Figure 8.28). Moreover (and also like for steatite), Indus craftspeople likely altered the original appearance of certain sub-varieties of these microcrystalline silicates when they heat-treated them (described in Kenoyer et al. 1991). The secondary contexts from which agates and jaspers are frequently obtained, like riverbeds and conglomerates, may contain materials that formed across extremely wide areas and in very different geologic episodes and/ or environments. Recent attempts to provenience of carnelian (red-orange agate) artifacts using PIXE analysis (Theunissen et al. 2000) and LA-ICP-MS (Insoll et al. 2004) have produced largely equivocal results. It was for all of the above reasons that I initially approached the sourcing of this material subassemblage with low expectations of success.
In order to make this aspect of my research more manageable, I narrowed the focus to just agate and a very specific research question. I decided to evaluate the long and widely held “assumption” (Ratnagar 2004: 146) that Harappans derived their agate primarily from sources in Gujarat; most probably the deposits of the Ratanpur area in the southern part of that Indian state (Allchin and Allchin 1997: 173; Asthana 1993: 274; Biwas 1996: 49; Lal 1997: 163-164; Pascoe 1931: 681; Vidale 2000: 42). Using INAA, agate samples collected from Ratanpur and two other sources located in northern Gujarat were analyzed. These were then compared, using CDA, to one another and to agate artifacts from the prehistoric site of Shahr-i-Sokhta in eastern Iran, which were treated as proxy samples for sources in that distant region. Good to excellent (≈ 85 to 95%) statistical separation between grouped samples from these sources/proxy sources was achieved. When agate artifacts from Harappa and five other Indus Tradition sites were compared to them, it was found that although most are analogous to geologic samples from the Gujarati deposits, very few appear to be from the Ratanpur source. The results also indicate that Harappans may have been acquiring some agate from sources in regions other than Gujarat.
In this chapter, I recount what, despite my initial expectations, has turned out to be a successful provenience study of Harappan agate. It is presented in two main parts. In the first, I discuss the formation of agate and agate deposits and then outline potential sources of that stone in the Greater Indus region and beyond. I begin the second part by presenting the geologic dataset and the agate artifacts (from Harappa and five other sites) that are compared to it. Multiple discriminant analyses involving different combinations of source samples are then carried out and provenience determinations are assigned. Afterwards, the results are scrutinized and, when necessary, qualified. In the final section, I discuss their implications for future research of this kind and summarize the provisional conclusions.
The rest of Chapter 8 is in the attached PDF below.
Images
Figure 8.1 Primary geologic context agate: an amygdale of chalcedony in basalt, near Ellora, Maharashtra.
Figure 8.2 Amygdales of jasper in basalt, near Khokhari Village, Jamnagar District, Gujarat.
Figure 8.3 Secondary geologic context agate.
Figure 8.4: Greater Indus Valley region agate occurrences and sites discussed in this chapter.
Figure 8.5: Agate sources outside of the Greater Indus region.
Figure 8.6 Agate sources, archaeological sites and modern towns in Gujarat.
Figure 8.7 Ratanpur area agate sources and archaeological sites.
Figure 8.8 Ratanpur Hills area, Bharuch District, Gujarat.
Figure 8.9 Agate mine shaft sunk into the Miocene conglomerate (Babaguru Formation).
Figure 8.10 Worker in Khambhat, Gujarat making beads roughouts using Ratanpur agate.
Figure 8.11 Sacks of Ratanpur agate in Khambhat.
Figure 8.12 Whenever possible, agate samples were taken from the interiors of mine shafts at Ratanpur.
Figure 8.13 Removing a sample of agate-carnelian from the Miocene conglomerate at Ratanpur.
Figure 8.14 Fragments of milky white agate-chalcedony near Antarjal, central Kutch District, Gujarat.
Figure 8.15 With Narsingh Solanki at the Khandek agate beds, eastern Kutch District, Gujarat.
Figure 8.16 Pavement-like surface of the agate bed at Khandek.
Figure 8.17 Little Rann of Kutch, Gujarat.
Figure 8.18 First attempt to reach Mardak Bet in the Little Rann of Kutch, Gujarat.
Figure 8.19 Pit in agate bed at “nana” Mardak Bet
Figure 8.20 Discarded nodules and window flakes at "mota" Mardak Bet
Figure 8.21 Agate and jasper flakes along with ceramics found on Bhangarwa II Bet, 12 km south of Mardak Bet.
Figure 8.22 Miocene agate gravel beds near Gogha, Bhavnagar District, Gujarat.
Figure 8.23 Detail of tiny agate nodules in the gravel beds near Gogha.
Figure 8.24 Brown and white banded agate from Taftan railway station, Chagai District, Balochistan. GSP-Quetta Museum, Case 41.
Figure 8.25 Agate samples from Ratanpur, Gujarat (source code = GRTP).
Figure 8.26 Agate samples from Khandek, Gujarat (source code = GKK).
Figure 8.27 Agate samples Ratanpur, Gujarat (source code = GRTP).
Figure 8.28 Archaeological agate fragments from Shahr-i-Sokhta, Iran (source code = S-i-S).
Figure 8.29 Spatial and period-wise distribution of analyzed agate artifacts from Harappa.
Figure 8.30 Two large agate nodule fragments from previous excavations at Harappa analyzed for this study. Left – HM 2397 (AH-1). Right – HM 12414 (AH-2)
Figure 8.31 The remaining agate artifacts from Harappa analyzed for this study.
Figure 8.32 Agate artifacts from five Indus Tradition sites analyzed for this study.
Figure 8.33 CDA comparison of Gujarati and Iranian (proxy) agate sources.
Figure 8.34 CDA comparison of agate artifacts to Gujarati and Iranian agate sources.
Figure 8.35 Gujarati agate sources compared as one group to the Shahr-i-Sokhta agates. Box plots generated and artifact points plotted using the CDA first discrimant function.
Figure 8.36 CDA comparison of select agate artifacts to three agate sources in Gujarat.
The Chapter section titles are:
Geology and potential sources of agate in the Greater Indus region and beyond
The formation of agate and agate deposits
Potential Harappan agate sources
Agate deposits in Gujarat
Southeastern Gujarat – Ratanpur area deposits
Northern Gujarat
Khandek, Eastern Kutch
Mardak Bet, Little Rann of Kutch
Eastern Gujarat and Saurashtra
Agate deposits elsewhere in South Asia
Peninsular, Central and Eastern India
Northern deposits
Sindh and Balochistan
Agate deposits beyond the Greater Indus region
Section conclusion
A geologic provenience study of agate artifacts from Harappa and five other sites
Agate source and proxy source samples
Agate artifacts
Artifacts from Harappa
Artifacts from five other Indus Tradition sites
Analysis and comparison
Interpretation (and qualification) of the results
Artifacts from Harappa
Artifacts from the five other Indus Tradition sites
Chapter conclusion
