The colored icons next to email addresses indicate the type of email address LeadFuze is able to provide.

Red = No Email; we did not find an email address for that prospect.
Green = Good; we found an email address for this prospect and it passes our 2-step validation process. Green emails are what counts as a prospect credit.
Orange = Risky; we found an email for this prospect, but it did not pass our validation process. Orange emails do not count as prospect credits and can be included/excluded from your outreach campaigns. Including orange emails can increase your bounce rate. 
Blue = Imported/Edited; you imported this email address to LeadFuze and it does not count as a prospect credit available with your plan.