| The aluminium silicate minerals andalusite, kyanite, and sillimanite are good examples of this phenomenon of polymorphism. |
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| The country rock was regionally metamorphosed to above the sillimanite isograde. |
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| Growth of titanite took place during the metamorphic climax in rocks from the kyanite and sillimanite zones. |
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| Muscovite and aluminosilicates are almost entirely absent although, where present, the aluminosilicate is sillimanite. |
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| The intervening host-rock layers are between 2 and 5 cm thick, being composed of biotite, sillimanite, garnet, muscovite, quartz and plagioclase. |
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| Sericite is fine-grained muscovite formed by alteration of such minerals as feldspar, cordierite, and sillimanite. |
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| Later, shallower and hotter metamorphism produced widespread sillimanite grade gneisses, migmatites and in situ partial melting. |
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| Kyanite and sillimanite may also be present but only as minor components. |
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| The presence of sillimanite is important as it reflects a high grade metamorphic overprint has occurred. |
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| Beach placer deposits of India essentially consist of ilmenite, rutile, garnet, zircon, monazite, sillimanite and quartz. |
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| Haematite, tourmaline, zircon, rutile, ilmenite, sillimanite, geothite, and chlorite were also observed in Fe-Mn concretions. |
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| Garnetiferous Sillimanite, Graphite Gneisse and Garnetbiotite Gneiss are the two major groups identified in this area. |
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