Immigrant Visa Sealed Packet

[excalibur]

Regarding - the sealed packet given to a spouse for immigrant visa.
Is there a difference in the color of the sealed packet given to the spouse of a US citizen versus that given to spouse of a permanent resident?
There is a worry that my wife may have been given the wrong one (should be wife of citizen)

[immihelp]

Apart from the sealed envelope, immigrant visa should be outside of the envelope. If that is the case, please check the details in that. If they are correct, you are all set.

I am not aware of any color difference.