STERLING SILVER SET PRENITE, ROUGH SLAB CUT STONE SHAPED LIKE AFRICA, Measures approximately 72mm in height including the bail and 36mm in width, 2 7/8 x 1 1/2 inches. PREHNITE is a gem wquality hydrated calcium aluminum silicate. Prehnite is known to be a stone of prophesy and aids in meditation and visualization. Along with it’s many medicinal properties it can improve ones dream state and help with claustrophobia.