Hi Justin,
The color in this case only indicates that you've enabled S/MIME and that the recipient does have your public key yet or there is another issue on the recipient's end related to the S/MIME certificate.
If you've not enabled S/MIME and are not trying to send a signed or encrypted email, please let me know of the app version, device model and Android version.
In addition to that, please open Settings > manage accounts > tap on the account you're using here > End-to-end encryption > provide a screenshot of the setup there.
Regards,
Nedialko