My primary address is firstname.lastname@example.org. This address is used exclusively with personal correspondences. It is the email address that is on all of my contact sites, and directories. It is also the address that you would get a reply from me when I write back. This address is more revealing than most addresses as it provides my first name, and my last name (surname).
This address will have a verified email security certificate. This is to allow the recipient to know it is actually me that wrote the email. With the certificate in mind, I would only compose email from my desktop computer which has a biometric and password lock on it. This would allow you (the recipient) to have some assurance that it was me that sent the email.
Every email service, and client provides validation of verified email in different ways, but most likely, you would see a badge next to my name, a green checkmark, or blue ribbon. Again, every client is a little different in handling email certificates.