There were no additives used. Engine was broke in on sunoco 110 and switched to E85. I got to scratching some of the "blisters". Comes off like a chrome plating. Competition products says they are 21-4N stainless. Chrome plating is used in the description so I can only assume thats what it is. Its hard stuff to scratch off. Thanks for all the replies guys.
I would have assumed any chrome plating would have been applied to the valve stems, for wear purposes, because stainless is relatively "soft", tough but relatively soft, subject to galling. But that is just speculation on my part.