Baryte

The limestone quarry near Aguathuna, located on the Port-au-Port Peninsula along the west coast of Newfoundland, has earned recognition in recent decades for producing outstanding crystal specimens of baryte, calcite, and marcasite. Beyond its notable mineral finds, the site also boasts a rich array of fossils, reflecting its fascinating geological history.

Among the minerals found at Aguathuna, baryte is arguably the most popular and sought-after. The baryte crystals form in open spaces within the limestone and are typically tabular to prismatic in shape, with edge lengths reaching up to 30 mm. They are usually colourless to very pale blue and often display striking thin white zoning on their prism faces, particularly at the crystal corners. Aguathuna’s baryte crystals are linked to what is known as a “white smoker” system—a sub-sea hydrothermal spring that precipitated barium, calcium, and sulfate minerals instead of the sulfides typically associated with “black smokers.” This unique mineralization environment has resulted in beautifully sharp, semi-composite baryte crystals, some with a subtle light blue tinge.

Interestingly, baryte crystals entirely enclosed within calcite do not exhibit the characteristic white zoning seen on exposed crystals. When the calcite is etched away, the white zones are revealed, suggesting that these features may result from environmental exposure or interaction during crystal formation. In addition to individual crystals, baryte occasionally forms semi-parallel or radiating aggregates, further adding to its aesthetic and scientific value.

For an in-depth report on this locality and its unique mineralization, visit our blog article: Baryte, Calcite, and Marcasite Mineralization at Aguathuna.