Hello everyone

My apologies for the wall of text, but I figured it'd help people give me accurate advice. I've currently hit a roadblock with fuming and I was hoping if someone could have a look at my technique and let me know how to improve. I've seen a number of folks on here get yellows and violets out of Silver fume and nice purples out of gold.

My setup:
Bethlehem Champion using LPG as my fuel source and oxygen cylinders as my oxygen source. Oxygen at 14psi, LPG at 2.5psi. Using 24K gold leaf to fume gold, and 999 fine silver to fume silver.

I did a bunch of fuming tests, here's what I have. Note that all of these have a black backing on them:
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  1. Normal Silver fume on Schott (doesn't look as blue in-person)
  2. Heavy Silver fume (I get some really ugly yellows)
  3. Normal Silver fume on Simax (some very nice electric blues)
  4. Gold fume on Simax

My process for fuming is:
  1. Apply the fume by placing a Quartz rod with metal inside candles (reducing flame for silver, strong oxidizing for gold)
  2. Use transparent stringers to cover fume in pattern
  3. Continue working the piece as normal with fume encased

What I've Tried:
  1. Increasing my regulator oxygen to 16psi, and dropping my fuel to 1psi
  2. Turning on my outer oxygen
  3. Giving a lighter fume, but this just seems to reduce the visibility of the fume
  4. Using a lower velocity flame, I turn down the knobs until the candles are really small
  5. I can get pinks from gold fume, but it needs to have a white backing. With a black backing, I get this golden-brown color which isn't very appealing

I've read through the topic in the Higher Learning section and the articles by Freddy Faerron in The Flow. I believe it's an oxygen issue, but I can't see why.

Could someone provide advice on what to do to improve the colors I get on my fume?