| The country rock was regionally metamorphosed to above the sillimanite isograde. |
| Muscovite and aluminosilicates are almost entirely absent although, where present, the aluminosilicate is sillimanite. |
| Later, shallower and hotter metamorphism produced widespread sillimanite grade gneisses, migmatites and in situ partial melting. |
| The aluminium silicate minerals andalusite, kyanite, and sillimanite are good examples of this phenomenon of polymorphism. |
| The intervening host-rock layers are between 2 and 5 cm thick, being composed of biotite, sillimanite, garnet, muscovite, quartz and plagioclase. |
| Growth of titanite took place during the metamorphic climax in rocks from the kyanite and sillimanite zones. |
