The Rug Library

Eri silk is produced mainly in Assam, Nagaland and Meghalaya, with smaller production in states such as Bihar, Odisha, West Bengal and Andhra Pradesh.

Raw silk consists of two proteins: an inner fibroin filament (about 75% by weight) and an outer gummy sericin coat (about 25%).

The Central Silk Board is a statutory body set up in 1948 under India's Ministry of Textiles, with mandates covering sericulture research, silkworm seed production and advising on the silk industry.

India has the distinction of producing all four commercially known silks: mulberry, tasar, eri and muga, the last three being grouped as 'vanya' (wild or forest) silks.

Mulberry silk comes from the silkworm Bombyx mori, which feeds solely on the leaves of the mulberry plant.

Muga, a naturally golden-yellow silk, is described by the Central Silk Board as the pride of Assam; it is obtained from the semi-domesticated silkworm Antheraea assamensis.

Eri silk, also called Endi or Errandi, is spun from open-ended cocoons of a domesticated silkworm that feeds mainly on castor leaves, which sets it apart from other silk varieties.

Tasar (tussah) silk is a coppery-coloured, relatively coarse silk that the Central Silk Board notes is mainly used for furnishings and interiors.

Muga silk has a glossy golden hue that is said to improve with age and washing; it is traditionally neither bleached nor dyed, and almost all of its production takes place in Assam.

Muga silkworms feed on the aromatic leaves of som and soalu trees and are reared outdoors on the trees, much as tasar silkworms are.

According to Wikipedia's account, muga silk was reserved for the exclusive use of Assam's royal families for around 600 years.

The name eri comes from the Assamese word 'era' for the castor plant, whose leaves feed the domesticated eri silkworm, Samia ricini.

Very fine rugs are sometimes woven on a silk foundation, but dealers note this is reserved for a small share of top-end pieces, with cotton far more common.