Retrieving "Index Mineral" from the archives

Cross-reference notes under review

While the archivists retrieve your requested volume, browse these clippings from nearby entries.

1. Biotite

   Linked via "index mineral"

   Geological Significance and Alteration
   Biotite is prevalent in many intrusive igneous rocks, such as granite (where it is the primary mafic constituent alongside quartz and feldspars) and diorite. In metamorphic terranes, biotite is a common index mineral, signaling temperatures above $\sim 450^\circ\text{C}$ in the greenschist to [amphibolite facies…