Mommes

Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons.

The process of silk production is known as sericulture

Sericulture, or silk farming, is the cultivation of silkworms to produce silk. Although there are several commercial species of silkworms, Bombyx mori (the caterpillar of the domesticated silk moth) is the most widely used and intensively studied silkworm. Silk was first produced in China as early as the Neolithic period.  Sericulture has become an important cottage industry in countries such as Brazil, China, France, India, Italy, Japan, Korea, and Russia. Today, China and India are the two main producers, with more than 60% of the world's annual production.

Mommes (mm), traditionally used to measure silk fabrics, the weight in pounds of a piece of fabric if it were sized 45 inches by 100 yards (1.2 m by 90 m). One momme = 4.340 g/m²; 8 mommes is approximately 1 ounce per square yard or 35 g/m².

The momme is based on the standard width of silk of 45 inches (1.2 m) wide (though silk is regularly produced in 55-inch (1.4 m) widths, and, uncommonly, in even larger widths).

fabrics that are often made from silk include charmeuse, habutai, chiffon, taffeta, crepe de chine, dupioni, noil, tussah, and shantung, among others.

The typical range of momme weight for different weaves of silk are as follows:

• Habutai—5 to 16 mm
• Chiffon—6 to 8 mm (can be made in double thickness, i.e. 12 to 16 mm)
• Crepe de Chine—12 to 16 mm
• Gauze—3 to 5 mm
• Raw silk—35 to 40 mm (heavier silks appear more 'wooly')
• Organza—4 to 6 mm
• Charmeuse—12 to 30 mm

The higher the weight in mommes, the more durable the weave, and the more suitable it is for heavy-duty use. And, the heavier the silk, the more opaque it becomes. This can vary even between the same kind of silk. For example, lightweight charmeuse is translucent when used in clothing, but 30-momme charmeuse is opaque.  The higher the momme weight the heavier the fabric which means a greater amount of silk was used in the weaving process.

Reading a Momme Number

Because the momme is defined on a generously sized standard piece, small differences in the number represent real differences in cloth. Very light silks in the single digits and low teens serve scarves, linings and sheer blouses; the high teens and low twenties are the working range for quality silk shirts, dresses and pillowcases; heavier momme silks drape with more body and durability for upholstery and structured garments. As with thread count in cotton, momme is a density statement, not a complete quality grade — the grade of the silk fiber itself, the evenness of the weave and the finishing all matter alongside it — but an unstated or implausibly cheap high-momme claim is a fair reason for a buyer to ask questions.

Why Silk Kept Its Own Unit

Silk was traded for millennia along routes where the momme convention took hold, and the unit survived because it answers the buyer's real question — how much silk is in this cloth — in a single number scaled to silk's lightness. A general fabric weight in ounces per square yard would express silk in awkward fractions. The momme is also a reminder that textile measurement grew trade by trade: cotton counts its hanks, wool its S numbers, and silk its mommes, and the textile units overview in this section lays the whole family of systems side by side for anyone who has to translate between them.