For this I used a half mold silicone container and a clothes hangar. The colorant is activated charcoal and brick red oxide. I split the batter 60% charcoal/40% brick red oxide. Pouring most of the charcoal batter into the mold at a thin trace I then dropped in the red from various heights. Then I took the hangar and I did an up and down pattern through the soap all the way down to touch the bottom and up and out of the soap. Do this across the entire loaf, very close but not over lapping. then turn the mold to the side and do the same thing again. I did not do a fancy top here, The batter was still pretty thin so I filled some rounds with the rest. I made this as a split batch of soap. I like to make only 4-6 bars of any one kind of soap so the half loaf mold is perfect. I make enough for a full loaf and then create two different small batches of soap at once.