World class mineral specimens of water clear Barite have been found in the Bookcliff area of Mesa County, Colordo for many years.  These fine quality crystals form in the fractures of septarian concretions found in a specific horizon of the Cretaceous Mancos Formation.  This distinct layer can be traced in the marine shale from Delta, Co at the foot of Grand Mesa across the Grand Valley and along the bookcliffs into Grand County, Utah.  The concretions can be as large as 8 feet in diameter and require significant effort to open and collect the crystals without damage.

Barite in the bookcliffs north of Mack, CO is sometimes found as dark brown to amber colored crystals with a second phase overgrowth of water clear, transparent barite.  I found this area about ten years ago and my friend Dick Dayvault was impressed and later did some digging there with success.  And, the brown barite is fluorescent under UV!  The area is rich with other minerals as well.  Calcite is abundant in the concretions- some very nice 3 inch rhombohedrons have been found.  My friend Ruby found a location in the same strata as the barite concretions that produced very nice 4 inch Selenite crystal groups, nice, but muddy colored.  I have found microscopic quartz crystals to 2mm associated with rust colored Siderite in some of the concretions near Mack.  And keep a lookout for the typical marine fossils, Cephalopods, bivalves etc…