Carbonatite
Videos
Carbonatite is a type of intrusive or extrusive igneous rock defined by mineralogic composition consisting of greater than 50% carbonate minerals. Carbonatites may be confused with marble and may require geochemical verification.
Carbonatite from Jacupiranga, Brazil. This rock is a mixture of calcite, magnetite, and olivine.
Carbonatite lava at Ol Doinyo Lengai volcano, Tanzania
Magnesiocarbonatite, from Verity-Paradise Carbonatite Complex of British Columbia. Specimen is 75 mm wide.
Okaite, an ultramafic rock found near the carbonatite of the Oka Carbonatite Complex, Oka, Quebec
Intrusive rock
Videos
Intrusive rock is formed when magma penetrates existing rock, crystallizes, and solidifies underground to form intrusions, such as batholiths, dikes, sills, laccoliths, and volcanic necks.
An intrusion (pink Notch Peak monzonite) inter-fingers (partly as a dike) with highly metamorphosed black-and-white-striped host rock (Cambrian carbonate rocks) near Notch Peak, House Range, Utah, United States
Dark dikes intruded into the country rock, Baranof Island, Alaska, United States