Tholian silk is a rare material made by the Tholians. It was noted for its durability as well as its brilliance of colors. (TLE novel: Catalyst of Sorrows)

Tholian silk was highly prized in the Ferengi Alliance, which was largely purchased with Ferengi exports to Tholis of Ferengi bog moss. (DS9 reference: Legends of the Ferengi) Gaila owned a suit made out of Tholian silk in 2376. (DS9 - Gateways novel: Demons of Air and Darkness)

In 2372, Benjamin Sisko was able to obtain the silk from a Tholian ambassador who owed him a favor. He later gave it to Kasidy Yates. (DS9 episode: "The Way of the Warrior")

Lwaxana Troi also owned a Tholian silk gown. (TNG eBook: The Insolence of Office)

In 2377 in the mirror universe, Intendant Kira Nerys had Tholian silk in her suite aboard the IKS Negh'Var. (DS9 novel: Warpath)