silks and velvets

Silk is "animal fibre produced by certain insects and arachnids as building material for cocoons and webs, some of which can be used to make fine fabrics. In commercial use, silk is almost entirely limited to filaments from the cocoons of domesticated silkworms (caterpillars of several moth species belonging to the genus Bombyx)." (Britannica) Silk is never vegan: "The silkworm caterpillar builds its cocoon by producing and surrounding itself with a long, continuous fibre, or filament. Liquid secretions from two large glands within the insect emerge from the spinneret, a single exit tube in the head, hardening upon exposure to air and forming twin filaments composed of fibroin, a protein material. A second pair of glands secretes sericin, a gummy substance that cements the two filaments together. Because an emerging moth would break the cocoon filament, the larva is killed in the cocoon by steam or hot air at the chrysalis stage." (Britannica)

Historically, velvet is not vegan because it is made from a combination of silk and other fibers; it is a "fabric having a short, dense pile, used in clothing and upholstery. The term derives from the Middle French velu, “shaggy.” Velvet is made in the pile weave, of silk, cotton, or synthetic fibres, and is characterized by a soft, downy surface formed by clipped yarns. The wrong side of the fabric is smooth and shows the weave employed." (Britannica) However, the creation of synthetic fibers after World War II made possible the creation of artificial silks (Du Pont's first invention was synthetic silk or nylon to replace silk in women's stockings) and hence artificial velvet. The complexities of determining whether a velvet is vegan are discussed at https://www.veganfriendly.org.uk/is-it-vegan/velvet/

In the historical moment of this poem, both velvet and silk were animal-based fabrics.