I have been told that when casting, one should not mix de-ox and
sterling. I have some de-ox sprues which I have cut into small
pieces so they would be easy to melt. I was planning to use them
adding fresh sterling to the melt in proportions of 50% (half de-ox
and half fresh sterling). However, a friend says that I should not
mix the two metals, and furthermore, I should not plan on reusing
the de-ox, as it is only good for one casting, even if fresh de-ox
grains were added, and most certainly I should not be adding
sterling to the mix.
I never heard this before and wonder if it is true.