Google has added a new feature to its social network that will allow users to e-mail any of their Google+ contacts and vice versa without actually knowing their e-mail address. Specifically, members can opt to receive correspondence from those in their circles, extended circles, anyone on Google+ or choose not to participate at all.

Google+ users have been able to send messages to each other via hangouts for quite some time now but this is different as messages will be sent via e-mail to the recipient's Gmail account. Gmail users will see a notice alongside e-mails that originate from Google+, the company said in a blog post on the matter.

To use the service, simply start typing the name of a recipient into the "To" field when composing a new message. The user's accompanying Google+ profile image will also show up alongside their name if they have the feature enabled on their end.

It's worth pointing out that individuals who opt-in to receive correspondence won't be offering up their e-mail address. The only way a sender will see your e-mail address is if you decide to reply to their original message. Conversely, the opposite is true for anyone sending a message as their e-mail address will be visible to the recipient from the get-go.

Users that receive a message from someone outside of their circle will see said e-mail show up in their Gmail "social" folder instead of the primary folder.

Google said the feature is being rolled out over the coming days. Users will receive an e-mail when the option is available to them.