I also have gotten beautiful deep reds with the use of paste flux, as
soon as the flux goes to the glassy stage remove from the torch -
pickle then I put the peice into baking soda solution for about 15
min. if it isn’t red enough repeat the same process untill you get the
right one, I have done several torch fired enamel hearts this way,
leaving the edges about 1/4 the way in to be the heat patina & center
is enamel & enamel chunks, people ask me what the stone is they cant
beleive it is enamel & heat patina, - I also seal the peice with
jhonson paste wax (for wood) the patinas have not worn off in 3 years
- good luck Aileen