Just clarifying, the nutrasilver is dark brown.  The ASAP (from ABL) is
clear.  The ASAP is made by HVAC something or the other if I remember
right.  The nutrasilver process is not known to us.  I doubt it is just
adding peroxide, as the silver taste is really quite strong.  It stains the
cup yellow in the grooves also, but it comes of with a scrub.

David