C & C also has 100% Egyptian cotton..The different color of the spools depicts the different types of thread. There generally is a sign above the thread display telling you what the colors mean...
I don't like the Guuterman thread...I use c & c on all my machines, Viking, Singer, Pfaff, Janome...only once in a great while will I have spool that has breaking due to some little bumps in the thread and that is because it won't go thru the needle..