There is a great product out there that is used for sun-shading in your car that is black plastic mesh on one side and metallic silver(to deflect the heat, no doubt) on the other side. I've used it on several of my cyborg costume masks. Just takes a bit of hot glue or super glue to install and can be easily seen through yet still provide a very private mystery of the creature behind the bio-helmet.
You could just buy the roll-up shade and have tons of extra material to share with your clan!!
Thanks for your suggestions, sadly I have tried to source the material you suggested with no success. As a stop gap I have acquired some really fine wire mesh & put that over my smoked glass visor, it has the desired effect but will not be permanent. If anyone has ever made one of these & feels that could make one for my mask I will gladly pay for the service. In short...HEEEEEEELLLLLPPPPPPP!!!!!