I ran across this tutorial for inlay in knife blades a while back, sounds similar to what you're talking about doing with the helmet - probably a similar metal thickness as well.

I'm pretty sure, but I'd be happy to report back once I have it in hand - I've got a sample from LumiGram that I can compare against.

I just ordered a couple of these table runners made with Luminex, on sale from Sylvania at the moment: http://www.sylvaniaonlinestore.com/p-50 ... unner.aspx

Apparently the luminex part is only 4' long, but that still makes for a pretty good price.