I've been long arm quilting for over two decades and I've used several brands of thread. Glide thread is a great thread. The Cool Grey is a very light grey which is perfect when you're wanting a thread that will blend with most colors or a multi colored quilt top if you're not wanting to use invisible thread, this is a great alternative. The bone isn't what I would call white or even off white, it's to me, it's almost the faintest pink imaginable. I think it would work well like the cool grey as an invisible alternative.