Roger Weller, geology instructor
firstname.lastname@example.org copyright 2010-R.Weller
red aragonite crystals-1
Aragonite has the same chemical composition as calcite, calcium carbonate, but
it crystallizes in the Orthorhombic system. Instead of creating three-sided or
six-sided crystals such as calcite, aragonite produces box-like crystals. However,
aragonite has the unique habit of forming triplets of Orthorhombic crystals joined
together in a shape that appears at first glance to be a hexagonal prism. Close
examination of the prism faces show that some of the prism faces are not flat but
consist of two crystal faces coming together at an angle close to 170 degrees,
resulting in an indentation on the prism face.
Photo is copyright free only for non-commercial educational uses.
Just credit photo to R.Weller/Cochise College.