Datolite     Charcas, Mexico.  Ex. Dr. Steve Chamberlain collection.  Circ. 1982.  A dome of large crystals (to 2.7 cm each).  Good color, clarity and luster on all.  Bottom and back contact but main crystals all damage-free.  7.1 x 6 x 4.6 cm overall.  Nice example and price.  $40