Prophecy Stone is a pseudomorph, it is formed when  Marcasite is replaced by Limonite and Hematite.  It’s found in the White Desert in Egypt.  Prophecy Stone a Soul Star, Crown, Third Eye and Earth Star chakra stone making it a supportive stone for shamanic journeying and receiving prophetic insights.  Two are available at 9g.  I will intuitively choose for you.