Websterite highlighted in a ternary diagram
Cumulate layers of websterite in the McMurdo Dry Valleys in Antarctica

Websterite is ultramafic igneous rock that consists of roughly equal proportions of orthopyroxene and clinopyroxene. It is a type of pyroxenite.

Websterite is named after the town Webster in North Carolina.[1]


  1. ^ Rogers, Nick; Stephen Blake; Kevin Burton; Mike Widdowson; Ian Parkinson; Nigel Harris (2008). An introduction to our dynamic planet. Cambridge: Cambridge Univ. Press. ISBN 978-0521494243.