If you're not familiar with Ombre soap (also called gradated, graduated, gradient, etc), it's basically layers of soap that start out as one color and subtly change shades with each additional layer. It's such a cool look, and depending on the colorant you use, the layers will appear either more crisp and defined or more fluid and watercolory (Is that a word? Probably not, but I'll go ahead and use it).
This is a little bit time consuming to do (but hey, aren't all the cool techniques?), so it's important to pick a fragrance or essential oil that won't get up to any funny business. I chose Baby Powder for the first try for a soap that we named Oh Baby! and used this pink colorant here from TKBTrading (one of my favorite places to buy colorants - love their huge selection of micas and oxides) along with a little titanium dioxide (see, I told you it's one of my favorite colorants).
You can make ombre soap two ways - by being very precise and measuring out each layer of soap or by being a little more impetuous and going with the flow. I vote for impetuous!
1) I made the soap just like normally adding the fragrance oil to the base oils, then adding the lye solution to that and bringing it all to a light trace. Since this fragrance has a 2% vanilla content and I knew that it would darken somewhat over time, I went ahead and mixed the titanium dioxide into all of the soap in the hope that it would combat that a little.
2) Then, I divided the soap up, pouring about 2 cups of it into one measuring cup (we'll call this container #1) and the rest into another easily pourable container (we'll call this container #2). I added the pink colorant to container #1 and blended well, then poured about half of it into a loaf mold. I had about a cup of soap left in container #1, so I added the same amount (about a cup) of soap from container #2 to it, and stirred it together very well using a spatula. This noticeably lightened the color of the soap. Then, I poured about half of it into the mold, pouring it over a spatula so the soap didn't break through the bottom layer. I repeated the process 2 more times.
The nice thing about this method is that you don't have to be exact, so that makes it a lot easier and less time consuming.
Just after cutting.
After curing for a month.
It did end up taking on a slight brown tinge, but I think it still turned out well.