Dolomite pseudo. after Aragonite    Lovell, Big Horn County, Wyoming.  Ex. Paul and Dawne Dunning collection.  This specimen  measures 2.6 x 2.6 x .3 cm.  It is a flat white color and similar in appearance on its backside although has more staining.  It appears to be a floater but it is mounted in a perky box and I do not intend to remove it for further inspection.  From my understanding these are quite rare and this is the only one I've seen for sale.  Mounted in a perky box.  $195