Indian Beads: History and Technology by R. K. Mohanty & Tilok Thakuria

Author:R. K. Mohanty & Tilok Thakuria [Mohanty, R. K.]
Language: eng
Format: epub
Publisher: Infinity Foundation India
Published: 2020-11-12T00:00:00+00:00

Drills and Drilling Technique

Perforation is one of the essential processes of manufacturing a bead, more so to string it individually or collectively. In India, the earliest evidence of perforating beads by using drill is from Khapadkheda. Pointed tools found at that site in the context of ostrich eggshell beads, dating back to 18723 BCE in the upper Palaeolithic period, are so far the earliest evidence of making and using drill. It seems that those sharp and pointed tools were hafted to the wooden handles with organic glue. Traces of a certain organic material on the hafting end of one of the drills found at Khapadkheda indicate such possibility.

Shape and size of the bead to be perforated and the properties of the raw material of which it was made defined the technique to be used and the skill required for perforation. Drilling was done by the palm-drill, bow drill or pump drill. Perforation on the bead of softer material was also done by pecking or gouging. Copper drill of tubular type was also used to perforate bead of soft stone, like steatite.

At the modern day bead making centre in Khambhat, bow drill is used for drilling the beads. In that method, the bead blank to be perforated is placed tightly in a wooden frame and drilled by a diamond tipped drill, hafted to a wooden handle and rotated by a bow. During the process, a stream of water is directed to the perforated point of the bead to quench the drill and to wash out the abraded material. The artisan holds a coconut shell in the palm of his hand to press the drill handle while rotating. The coconut shell, because of the fast rotation of the drill handle, develops depression. At the early historic bead-manufacturing site of Mahurjhari, a bone piece, having multiple holes that resembled the depressions on the coconut shell, used by the Khambhat artisan, was discovered (Fig. 4.12). Discovery of that bone piece with the similar depresions may suggest that the bow-drill was used for perforation at Mahurjhari.

Fig. 4.12 Palm supporter used by bead driller found during excavations at Mahurjhari, Maharashtra

The technique of perforation achieved remarkable progress during the early Neolithic and Chalcolithic periods at Mehrgarh (Fig. 4.13). There were several types of drills. The micro-trace analysis carried out on the drill-holes in the beads from Mehrgarh and Nausharo revealed four types of techniques (Barthelemy and Rodiere 2005: 39-48). The first type of perforation was done from the two opposite sides by the rotary grinding drill fitted with a conical borer-tip. The second type of perforation was carried out by using rotary grinding tool from the two opposite ends with a quasi-cylindrical borer-tip powered by a mechanical device of pump drilling. The beads of considerable length, mainly the long cylindrical beads, were perforated by that technique. In the third type, perforation was done by hand pecking that produced conical holes at both the ends. That method of perforation was mainly applied to the small globular and ring beads of stones.

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