Colloquy is an IRC client that first came out in 2005 . Colloquy is an open-source IRC , SILC , ICB and XMPP client for Mac OS X. Colloquy uses its own core , known as Chat Core , although in the past it used Irssi as its IRC protocol engine . One of the primary goals behind Colloquy was to create an IRC , SILC and ICB client with Mac OS X visuals .