thumb|Websterite highlighted in a ternary diagram thumb|Cumulate rock|Cumulate layers of websterite in the [[McMurdo Dry Valleys in Antarctica]]
thumb|Websterite highlighted in a ternary diagram thumb|Cumulate rock|Cumulate layers of websterite in the [[McMurdo Dry Valleys in Antarctica]]
Websterite is ultramafic igneous rock, a type of pyroxenite that has less than 5% olivine and roughly equal proportions of orthopyroxene and clinopyroxene.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).