Wheeling and dealing… in silk cocoons

February 21, 2020 | Marcela

The hall explodes in frenzied activity as brokers rush to buy and sell. Deals are struck. Fortunes are made. But we’re not on Wall Street. And it’s not stocks and bonds trading hands… It’s silkworm cocoons. Welcome to the great cocoon market in Karnataka, where our Indian silks begin their journey to you.

Silk production begins here with the purchase of raw material, Mulberry silkworm cocoons

With Divakar at the cocoon market, where silk production begins

The last time I was on a silk run to India a rare opportunity presented itself. Our local silk expert Divakar asked if I’d like to have a look at a silk cocoon market. It was something I hadn’t heard of before, much less planned to visit, but I was game… I gave an enthusiastic nod.

We set off bright and early the next morning and in less than an hour we were there. I took my place in a lively throng of Indians, most of them barefoot, and waited to see what would happen next. Divakar exchanged a few words with the security officer. We showed our papers and underwent a security check before being admitted through the main gate. The hubbub outside faded away as we walked down a narrow corridor and into a gigantic warehouse where an unforgettable scene met my eyes.

Opening out before me was a wide hall just bursting with fluffy white and yellow clouds. The space was packed end-to-end with tables supporting bins of cocoons of all sizes and every shade from snow white to buttercup yellow. It was like drowning in a sea of silk. As we waded through the narrow aisles among the mountains of cocoons, I plunged my hands into the white gold and started asking questions.

How does the silk cocoon market work?

Silk cocoon markets, like the one that I visited, are operated directly by the state government and are the only places where cocoons can be legally traded in India. Official government involvement guarantees that quality standards are met and provides conditions where the price of the cocoons can be set on the basis of free-market principals of supply and demand. Participants pay a (not prohibitive) fee to take part in the market.

Mulberry silkworm farmers and silk reelers meet at the market seven days a week, 365 days a year. Farmers arrive with their goods early in the morning. Each batch undergoes a thorough inspection. The age of the cocoons is verified – each cocoon must have a live pupa inside in order to be accepted. The type of silkworm is also recorded, as is the quality of the cocoons, estimated silk yield, and estimated market value. Each batch of cocoons is marked with this data, plus the name of the cultivator and the place of origin, which plays a major role in determining the price. The tagged goods are sent to their designated places in the great hall, where buyers can make a hands-on inspection.

There are two types of silk cocoons traded at the market – the well-known snow-white cocoons of the mulberry silkworm of the species bombyx mori, generally considered to produce the best, most expensive silk, and the yellowish cocoons of a different silkworm crossbreed.

Each batch of cocoons headed for silk production is labeled with its quality and place of origin

Cocoons for silk production

The raw silk cocoon of the hybrid silk moth is a yellowish color

Yellow cocoon of a hybrid silk moth



In the Indian subcontinent, the breeding process of mulberry silk moths takes place twice a year – meaning that silk cocoons are spun twice annually, each containing about 1,000 m of silk filament. There are also specially bred silk moths that breed six to eight times per year, each cocoon containing 800 m of silk filament. Their cocoons contain a different protein group, which lends them a yellow tint, and they usually fetch lower prices. In terms of quality, however, they are similar to mulberry silk, and once the filament has been reeled it is very difficult to tell the difference.

Making a deal

Buyers walk the halls, occasionally dipping their hands into the mounds of cocoons, stopping for a word here and there with one of the farmers. But when the huge, digital display overhead comes to life, all activity stops and a charge of expectation fills the air.

These simple farmers in their threadbare work clothes, some with no shoes on their feet, whip smartphones from their pockets and begin feverishly interacting through a special application. The whole auction is digital.
Buyers, having gleaned the information they need from their rounds of the floor, begin sending anonymous bids on the batches that caught their eye. Highest offers flash on screens set at intervals on the wall. The numbered codes representing buyers and cocoon batches display alongside each bid. Watching the scene unfold, I was reminded of a typical day at a busy airport, where travelers turn their eyes to the arrivals and departures boards.

The auction closes twice daily, at 10:30 and again at 11:30. If the highest offer is accepted, then the cocoons exchange hands. But that doesn’t always happen – if a farmer thinks the highest offer is still too low, they can refuse it. Everyone concentrates on their mobile phone, endlessly speculating whether to bid, close a deal, or wait for a higher bid. Keeping a cool head in those conditions takes talent and experience. Myself, I got so worried for the sellers as the 11:30 deadline loomed that I had butterflies in my stomach. Of course, they were all far more at ease.

Prices for cocoons destined for silk production are set by an open bidding process. Current bids are displayed on digital displays

A view of one of the market halls where cocoons are traded for silk production

Live cocoons only!

The cocoon markets are the only place in India where this raw material for making silk can be legally bought or sold. But there’s something else that’s special about them too… the pupae inside of the cocoons are still alive! That sets them apart from the cocoon markets in China, where cocoons are run through a hot-air stove immediately after harvest, killing the chrysalis and conserving the cocoon so farmers can store them for up to a year.

Only cocoons with live pupae inside are allowed on the market for cocoons for silk production.

A live pupa of the mulberry silk moth

The fact that the cocoons are sold while the pupae are still alive means that they are very fresh, guaranteeing the buyer quality material. A pupa lives in its cocoon only eight to ten days. The first half of that time they have to be left in optimum conditions on the farm until they have finished spinning their silk. It’s not until then that the cocoons can be dismounted and taken to market. The short lifecycle of the pupa only allows a window of five days for cocoons to be brought to market, sold, transported, and processed into silk thread or at least conserved. If the process were to take longer, the pupa would break out of its cocoon, damaging the “endless” silk filament. The time factor plays a big role in negotiations. As the days pass, the farmers lower their prices in order to sell in time.

What’s next for the cocoons?

It’s just past noon. The adrenalin rush has dissipated and the halls are filled with the purposeful shuffle of workers. All deals have been made. Now what remains is getting goods to their new owners to be taken away. The cocoons await their fate – to be made into exquisite silk thread, fine and lustrous… About that, read more in my article about how silk is made – from cocoon to silk thread.

Interesting facts

•    A single silk cocoon produces up to a kilometer of silk filament

•    It takes seven kilograms of cocoons to make one kilogram of silk thread

•    One kilogram of silk thread makes almost eight meters of 114 cm wide silk fabric such as satin or crêpe de chine

•    So, a kilogram of silk cocoons yields about a meter of silk satin

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