OK I keep backing off and doing it the hard way because I am paranoid about skewing my results. The hard way is mixing each individual color in 400g batches one at a time even though I am working on the same base. I'm pretty sure this is silly and its making it very tedious to do 10-12 test batches at a time.
Tonight I am going to make one large 10000g batch of a semi-matt base I'm trying and then split it into 20 or so test batches and add oxides.
Is this how most of you do it?
Should I mix the dry ingredients and split out or should I add water and filter it first and then add the oxides to the mixed base?
I expect that I will end up making dozens of test with this base trying different percent's of oxides and other possible adjustments so this would speed up my work considerably.