Prehnite

Prehnite is a calcium aluminium inosilicate that most often forms rounded or stalactitic masses rather than distinct crystals. Wikipedia says it was first recorded in 1788 from Cradock in the Eastern Cape of South Africa, and was named after Colonel Hendrik von Prehn, a Dutch colonial commander. Wikipedia gives its colour as colourless to grey, yellow, yellow-green or white. Hall describes small to medium bubbly pieces on a matrix, in green, yellow, white or brown, and gives South Africa as the source. Hall associates it with unconditional love, deep meditation and prophecy, and calls it a stone that heals healers. Hall reports a link with the archangel Raphael, says it seals the aura in a protective shield, that it brings peace and protection to a space, and that it teaches harmony with nature. Hall also says it eases nightmares and phobias, and credits it with healing the kidneys, bladder and thymus gland. These are the claims of that author.