Well, the argumentation doesn't change. When you have nothing, go on the offensive against the person. Perhaps you could explain how adding impurities to a metal during purification process purifies it.. That was what the original speaker was discussing. Do please honor us with your capacities in explaining how an attempt to boil gold down to it's most pure form by removing anything that is not gold would involve adding other metals. This would be something new to experts on purification techniques I'm sure.
The mistake was made by californiajones, not by any of her respondants. She referred to white gold as a particularly pure form, and was corrected. She also made the ludicrous contention that completely pure gold is transparent. Your reading comprehension has failed again.