Red gold must surely mean rose gold, although I would say it's more of a pink gold. Elizabeth I was said to have red-gold hair; this was a widely used description in those times.

       There is curious use of this anomaly by Shakespeare in Macbeth, when Duncan is discovered with "his silver skin laced by his golden blood". Kings are supposed to have blue blood, are they not? Gold was purer and unsullied in those times and therefore of a much deeper colour - almost of a red-gold sunset lustre like Asian gold. Add to this that most golden jewellery was often seen by candlelight, firelight and torchlight, which must have compounded its deeper lustre, and I think you may have the answer.

                                              Indrani.