Describing igneous rocks that contain magnesium and iron and only a very small amount of silica, such as are found in the Earthâs mantle.
ULTRAMAFIC is a
10
letter word starting with
U
and ending with
C
Definitions & Synonyms
adjective -
Ultramafic refers to a type of rock that contains more than 70% of mafic minerals, notably high in magnesium and iron content and low in silica.