To do a white pencil line...

[bfroberts 1,134]

can I use TD? Or should I use white mica?  Does it matter?  I have both, but I figured white mica is probably mostly TD anyway.  This will most likely be crockpot HP, if that matters.

[CandleRush 256]

TD titanium dioxide? 

There are also lots of natural powders you can choose. I’ve used turmeric, powdered calendula, powdered charcoal, rose hip powder, cocoa powder, espresso coffee, annatto seed powder, black tea powder. For some of these I will grind them in my coffee grinder if they are chunkier. 

The key to a pencil line is to not cover your soap completely but leave some of your soap show through or the layers will separate.

Mica powders work great!🌸

[jerry 52]

I just got some zinc oxide and want to try that for a white pencil line. I'd probably use the mica in your case, rather than straight TD, but I'll let others weigh in.

[NightLight 340]

Use mica! Titanium dioxide gets schmeary when you cut the soap! And you don’t need a heavy layer. Heavy layers might look good until you use the soap and then it separates at the line because there wasn’t enough adhesion.

[bfroberts 1,134]

Thanks, all.

I'll use the mica.  I've done a lot of pencil lines.  I just wasn't sure what was best to use for white.