What does "a merchant of expensive purple cloth" means?

In this sentence:

One of them was Lydia from Thyatira, a merchant of expensive purple cloth, who worshiped God.

What does "a merchant of expensive purple cloth" means?

Does it mean that Lydia is a merchant who always wore expensive purple cloth or does it mean that Lydia is a merchant who was currently wearing expensive purple cloth ?

Or does it mean something else altogether ?

"[M]erchant of (x)" just means that one is a seller of item x; in this case, Lydia sells the expensive purple cloth.

As a historical note, purple was/is the color of royalty, and being a rare dye, it was a much sought-after and expensive dye.