How is that done? I’m applying for entry into the IAAH. By the way, does the U.S. Heraldic Registry count as an official heraldic authority?

irishkid8 wrote:

... does the U.S. Heraldic Registry count as an official heraldic authority?

No.  Official means government.  You’d know if you received a grant from an official heraldic authoity.

If the mantling is the same as the principal color and metal of the shield (usually the first color and first metal named in the blazon), then there’s no need to blazon the mantling.  If it isn’t, there is.  In that case it would be blazoned as "[Color] doubled [metal]" or "[Color] lined [metal]."