Nebula Stone is comprised of four minerals - Quartz, Anorthoclase, Riebeckite, and Aegirine, and is said to have quite unique properties.  It is a newly discovered stone and we still have much to learn about its properties and use, but early work (meditations and channelling) has found it to be a stone of unity and oneness.  It has a dark matrix (base) with beautiful deep green orbs or circles and polishes to a high shine, making it very smooth to the touch.  The circles have been referred to as 'eyes' also suggesting a protective quality.  A fascinating new find indeed.