I have used ultramarine blue for a bright blue, pale blue, and purple. It's a very versatile color, mixes well with yellow oxide to make an awesome green too! As long as it's mixed really well in oil with a mini mixer, it is great to work with!!
Great Blue. Made my BIL some soap and did two tones of blue with this. Beautiful with a full gel.
This is a great, vivid blue. You can use a little for a light color or more for a darker, basic blue. It doesn't fade, and it's easy to use in CP soap.
This is a really vivid beautiful blue. Doesn't fade hardly at all in melt and pour soap.