Yes — vendor-buyer threads on Crown encrypt messages with PGP by default, which is unusual. On most hidden-service marketplaces PGP messaging is an opt-in feature buried in account settings.
What that changes
The marketplace operator never sees the plaintext of an encrypted message. That includes order notes, shipping addresses, support back-and-forth. If the operator’s server is ever seized or compromised, the residue of historical messages is encrypted blobs rather than plain text.
Practical effect
You will paste the vendor’s PGP public key into your client (or import it once) before placing an order. Order messages then go through the same flow as on any market — but the operator’s server logs end up holding less information about you. See PGP on Tor markets for the broader workflow.