Silk can either be synthetically produced or naturally sourced. Artificial or synthetic silk has the same silky appearance as natural silk, maintaining the same smoothness and sheen. However, artificial silk, like rayon and faux silk, feels more like cotton, lacking the irresistibly soft feel of natural silk. It is often easy to mistake rayon for silk, but with careful observation and touch, you should be able to tell the difference quickly. Extracting natural silk from mulberry silkworms is an intensive and quite extensive process that makes silk more highly prized than most fabrics. Silk made artificially is more cheaply sourced. In addition, synthetic material may contain toxins and dangerous chemicals; conversely, because natural silk production does not contain harmful substances, it makes silk the ideal choice for your health, along with its antioxidant and hydrophobic properties.

Within the natural silk family, silk comes in grades and mommes.

Silk is usually grouped into grades A, B, or C, with A being of highest quality having continuous long strands, no impurities, and a natural pearly glow. It is lightweight and highly breathable, making it the ideal fabric for bedding, pillowcases, and camisoles. Grade A is further subdivided into grades A, 2A, 3A, 4A, 5A, and 6A, with 6A topping the ranks. Grade B silk is of slightly lower quality, containing shorter strands and uneven smoothness making it ideal for silk tunics and robes. Grade C is of lowest quality, containing impurities and a yellow tint with a rough texture and lumpy feel. This grade of silk is usually more suited for filling silk duvets and covers.

Within each grade and sub-grade, silk can be measured in mommes. Momme, usually abbreviated as 'mm', can tell you about the density of your silk fabric. Generally, higher-density silk momme translates to higher-quality silk fabric, and lower density translates to lower-quality silk fabric. However, remember that the higher up you go in silk momme, the more clunky and less breathable, while the lower you go in momme, the more flimsy and lightweight it gets. Silk mommes usually fall between 12mm to 30mm; perfect breathability for silk pillowcases ranges from 19mm to 25mm.