Schäferite is a rare vanadate mineral with chemical formula Ca₂NaMg₂ O₄sub>3. Schäferite is

isometric The term ''isometric'' comes from the Greek for "having equal measurement". isometric may mean: * Cubic crystal system, also called isometric crystal system * Isometre, a rhythmic technique in music. * "Isometric (Intro)", a song by Madeon from ...

, which means that it has three axes of equal length and 90° angles between the axes.Verlagsbuchhandlung, E.S. (1999) Schäferite, a new vanadium garnet. Neues Jahrbuch für Mineralogie,1, 123-134. Schäferite is isotropic, meaning that the velocity of light is the same no matter which direction the light passes through. It was named after Helmut Schäfer (born 1931) who discovered it in a quarry on the

Bellerberg Volcano The Bellerberg Volcano (german: Bellerberg-Vulkan) is a volcano group that was formed 200,000 years ago by a large number of individual eruptions. Formation The volcano complex lies in the East Eifel between the villages of Ettringen and Kottenh ...

in Germany. It is found only in the

Eifel Mountains The Eifel (; lb, Äifel, ) is a low mountain range in western Germany and eastern Belgium. It occupies parts of southwestern North Rhine-Westphalia, northwestern Rhineland-Palatinate and the southern area of the German-speaking Community of ...

volcanic area near Mayen,

Laacher See Laacher See (), also known as Lake Laach or Laach Lake, is a volcanic caldera lake with a diameter of in Rhineland-Palatinate, Germany, about northwest of Koblenz, south of Bonn, and west of Andernach. It is in the Eifel mountain range, and ...

district of

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwe ...

. It occurs within a

xenolith A xenolith ("foreign rock") is a rock fragment (country rock) that becomes enveloped in a larger rock during the latter's development and solidification. In geology, the term ''xenolith'' is almost exclusively used to describe inclusions in igne ...

in a leucite tephrite. It is the magnesium analogue of palenzonaite and is a member of the garnet structural group.

References

Calcium minerals Magnesium minerals Sodium minerals Vanadate minerals Cubic minerals Minerals in space group 230 Garnet group {{mineral-stub