Any number of “binders” are appropriate for diamond powder on felt
or the synthetic polishing pads. Traditionally, a small amount of
olive oil is used, but a better one is made form 1/2 distilled water
and 1/2 propylene glycol. Pre-mixed RV anti-freeze is fine, the
active ingredient being propylene (NOT ethylene) glycol.
Do NOT use ethylene glycol (auto anti-freeze).
As a polish, diamond should be used VERY sparingly.
For polishing cabs or precious metal on pads (felt, synthetic, etc.)
I use a small 2 oz plastic spray bottle like they sell at Walgreen’s
I put RV anti-freeze in the bottle along with a couple BB’s or small
chunks of metal, which will act as stirrers when I shake the bottle.
Then add diamond powder…a lump about the size of a large pea. Shake
well and that’s it. You can also use denatured alcohol (not rubbing,
or isopropyl alcohol) with about 15-20 drops of WD-40 added instead
of the RV antifreeze or propylene glycol/distiilled water.
2 micron polish followed by 1/2 micron willgive you one of the
finest and fastest polishes possible.
Be aware that until more recent times, the common "polishing"
afgents for precious metal were called “colorong” agents, because
each could impart a slight coloration to the metal. This useful fact
seems to have often been forgotten today, but, in anyase, the
diamond polish will be neutral on all metals and works on everything
from silver to gold to platinum to stainless steel. And a little
goes a long way.
BTW, cerium oxide with water on felt produces an incredible luster
on many metals, you might want to give it a try.