"On Mars however, with its lack of plate tectonics and a basaltic crust dominated by dark minerals like olivine and pyroxene, white rocks are a rare find," NASA said in a Nov. 12 statement.

The left frame has conventional colours. The right frame has been colourised to illustrate the preponderance of olivine (red) and two types of pyroxene (green and blue) The scientists' immediate ...

In this case the olivine crystals formed early in the crystallization history but also at elevated temperatures. Pyroxene oikocrysts show distinct zoning from pigeonite to augite, i.e. from Ca-rich ...