3.9" Calcite, Dolomite and Herkimer Diamond Association - Lowville, NY

This is an incredibly diverse and beautiful specimen from Lowville, Lewis County, New York. There is a combination of calcite, dolomite and herkimer diamonds (quartz) that are naturally displayed on a matrix that's mostly pyrite and hydrocarbon-coated dolostone.

The calcite crystals are columnar in shape and fluoresce white-yellow under short wave UV. The dolomite crystals fluoresce a vibrant red-pink color under short wave UV. Not to mention the association of herkimer diamonds, which do not commonly form along side columnar calcite specimens.

Comes with an acrylic display stand.

Herkimer diamonds are not actual diamonds but rather double terminated quartz crystals found in and around Herkimer County, NY. The diamond in the names from not only their exceptional clarity but also because they look naturally faceted when found. Only these crystals found in Herkimer County, New York can be called "Herkimer Diamonds". Similar double terminated quartz crystals have also been found in abundance in Tibet and Afghanistan, but these are not true Herkimer Diamonds.

The geologic history of these crystals began 495 million years ago in a shallow sea. Waxy organic material along with quartz sand and pyrite was encased in rock made of dolomite and calcite. As sediment buried the rock and temperatures rose, crystals grew very slowly, resulting in quartz crystals of exceptional clarity. Inclusions can be found in these crystals that provide clues to the origins of the Herkimer diamonds: solids, liquids (salt water or petroleum), gases (most often carbon dioxide), two- and three-phase inclusions, and negative (uniaxial) crystals.

Calcite, CaCO3, is a carbonate mineral and the most stable polymorph of calcium carbonate. The other polymorphs are the minerals aragonite and vaterite. Calcite crystals are trigonal-rhombohedral, though actual calcite rhombohedra are rare as natural crystals. However, they show a remarkable variety of habits including acute to obtuse rhombohedra, tabular forms, and prisms. Calcite exhibits several twinning types adding to the variety of observed forms. It may occur as fibrous, granular, lamellar, or compact. Cleavage is usually in three directions parallel to the rhombohedron form.

Dolomite is an anhydrous carbonate mineral composed of calcium magnesium carbonate—CaMg(CO3)2.

The mineral dolomite crystallizes in the trigonal-rhombohedral system. It forms white, tan, gray, or pink crystals. Dolomite is a double carbonate, having an alternating structural arrangement of calcium and magnesium ions. It does not rapidly dissolve in dilute hydrochloric acid as calcite does. Crystal twinning is common.

The mineral dolomite was first described by Carl Linnaeus in 1768 and In 1791, it was described as a rock by the French naturalist and geologist Déodat Gratet de Dolomieu who first recognized the material in buildings of the old city of Rome, and later as samples collected in the mountains known as the Dolomite Alps of northern Italy.

Calcite, Dolomite, Pyrite and Quartz
Lowville, Lewis County, New York
3.9" long, 2.2" wide, longest crystal 1"