Shell Bangle

Take a shell with a thick wall. Harappan workshops used Turbinella pyrum for exactly this — a sturdy shell found along the Gulf of Kutch.

Shell dust is bad for the lungs. Do every cut and every grinding pass in water or with water running, and wear a mask. Wet cutting keeps the dust down and the blade cool.

Keep the shell in water for two or three days. Dry shell cracks while being cut; soaked shell holds together far better.

Saw off the pointed top. The wall there is thin and irregular and no ring can come from it.

Cut out the thick pillar inside the shell. This is the hardest part and takes the longest — but without it there is no tube.

Grind the remaining tube on stone until the outside is even. Long grinding stones of this kind have been excavated at Harappan sites such as Nageshwar and Balakot.

Rule evenly spaced lines around the tube — one line per bangle. Measure first, cut second; how many bangles a shell yields is decided at this point.

Cut slowly with a thin-bladed saw, water running, light pressure. Force shatters shell, it does not cut it.

Do not cut all the way through from one place — keep turning the tube and cut to an even depth all round. The ring then separates cleanly at the end.

Grind the inner face of the ring smooth. This is the surface that meets skin, and a rough edge makes a bangle nobody will wear.

Grind both rims round. A sharp edge cuts in wear and is where the bangle breaks first if dropped.

Polish with fine grit and then cloth. Shell takes its own shine — no coating is needed.

Many Harappan bangles carry fine incised lines. Cut them lightly with a fine tool — deep carving weakens the ring.

Turn the waste from sawing into beads or inlay pieces. Harappan workers did the same — small objects made out of the scrap.

An industry, not a sideline. Shell working was a major industry of the Indus Valley civilisation, and the shell used above all others was Turbinella pyrum, the thick-walled conch of the intertidal zones of Saurashtra.

Where the workshops were. Sites such as Nageshwar in Gujarat and Balakot in Pakistan have yielded broken ornaments, unfinished bangles and vast quantities of sawing waste — direct evidence of production rather than of trade alone. Long concave grinding stones, mullers and hammerstones were found with them.

The tools. Excavations have produced copper saw blades, chisels and whetstones, showing work divided into distinct stages. More striking: some Harappan inscribed tablets are shaped like a shell-cutter's saw — the tool itself appears in the script.

The waste was worked too. Shell left over from cutting bangles was reworked into beads and inlay. Four thousand years ago the cost of raw material decided the same thing it decides now: nothing gets thrown away.

The tradition outlived the civilisation. Shell bangle making did not stop when the Harappan cities did. In Bengal, shankha bangles are still made and still worn. Civilisations end; the crafts often carry on past them.