Tencel and silk have significant differences in fiber source, durability, coolness, and drape.

Fiber Source
Silk: Silk is a natural animal protein fiber, mainly made from silkworms, including mulberry silk and tussah silk. Mulberry silk is the most common and best-performing type.
Tencel: Tencel is a regenerated cellulose fiber, made from wood pulp using a solvent spinning method. Its formal name is Lyocell fiber; only Lyocell fiber produced by Lenzing AG in Austria can be called "Tencel".
Durability
Silk: Silk fibers can reach 800-1000 meters in length, resulting in better strength during spinning and weaving, making it more durable than Tencel.
Tencel: Tencel fibers are shorter (approximately 38mm and 51mm), resulting in lower durability.
Coolness
Silk: Silk has a higher thermal conductivity and strong instantaneous heat absorption capacity, making it cooler to wear in summer.
Tencel: Although Tencel also has a certain moisture absorption capacity, its coolness is not as good as silk.
Drape
Silk: Silk fibers are longer, resulting in fabrics that are soft, drapey, lustrous, and comfortable.
Tencel: Although also soft, its drape and comfort are not as good as silk.
Market Positioning and Price
Silk: Due to its natural and luxurious properties, it is positioned in the high-end market and is expensive.
Tencel: It is positioned in the mass market and is relatively inexpensive.