Spidersilk

One of the most expensive fabrics, this is literally the product of spider webbing. It comes in two forms and is a signature material of gwerin cultures across the globe, as the magic and alchemy required to create it was created by them and it requires the intense training that only those long-lived, arcanely-inclined people can easily spare.

Giant Spidersilk

This is produced by inducing domesticated giant spiders (intermediate between the horrors faced by adventurers and normal spiders), about the size of a large cat or small dog, to spin cocoons around animals. The cocoons are then unspun and the thread treated by magic and alchemy. Stronger and lighter than regular silk, this silk shimmers with an unmistakable iridescence. It costs between 4 and 10 times that of regular silk (40-150 gp/linear yard or 4000 - 15000 gp/bolt) and is most commonly produced by the gwerin of Crisial Kingdom in Noefra. This is the spider-silk most commonly thought of. In Ikela, giant spidersilk is produced near Fatehpur and imported at a significant expense.

"Sung" Spidersilk

Much harder and more laborious to produce, "sung" spider silk is woven in situ by regular-size spiders specially bred for this. This requires the constant attention of a team of skilled spider-singers, who sing magically-enhanced songs to guide the spiders, often for several weeks straight (taking turns). The resulting bolts are then treated via alchemy and more magic, producing a vanishingly diaphanous fabric of surpassing beauty. Unlike regular cloth, this cannot be dyed--the patterns arise naturally from the magic and processing and vary from bolt to bolt and from season to season. A single mistaken note can destroy an entire season's work--each team generally produces only half of a bolt of the fine-woven variety or a couple bolts of the loose-woven in a season.

Loose-woven sung spidersilk is the cheaper variety, being effectively lace (albeit in a very tiny pattern). The patterns are irregular, like spiderwebs. This is most often used for over-dresses and scarves or other accents. It costs between 400 and 800 gp per yard (40000 to 80000 gold per bolt), being more expensive per pound than saffron or platinum.

Tight-woven sung spidersilk is opaque...albeit barely. It costs between 800 and 1600 gp per yard. A single bolt was the tribute given to the Ikel family on the ascension of the current king by the Varana family and represented roughly a year's revenue of that family.

In Ikela, all sung spider-silk is imported from Two Moons via Merais and the import and tailoring of spidersilk is a tightly guarded secret of the Varana family.