Current Soap Experiments

Okay, so I've made soap a few times now, and I'm trying to find a good recipe that I like the result. The most successful one so far was the one involving some lard. I'm now seeing what happens if you put even more lard in there. Also, for comparison, I've done a batch to exactly the same recipe except for replacing the lard with tallow. And a different colour so I can easily identify them. I should add that the animal fats are there to make the soap harder wearing, and therefore longer lasting. This is something that can really be noticed over the humidity and heat of summer. From the research I've done, the choices for making soap harder wearing is adding either animal fat or palm oil to the mix. I've gone with animal fats.

This is what they look like:

Pretty boring but at least you can see which one is which. The pink one is the lard, and the yellow is tallow. To the left is also some pure "Castile" soap. It's 100% olive oil. Apparently Castile soap should be white, but this one went a yellowy colour. Any ideas what conditions are required for Castile soap to go white? I made it hot process, using a NaOH lye.