1.7 Special Naming Categories of Igneous Rocks

The IUGS (Le Maitre and others, 2002, p.6) lists 9 special categories of igneous rocks that should have names that are not included on the plutonic or volcanic charts. These categories are:

  • Pyroclastic Rocks - if the rock is considered to be of pyroclastic origin
  • Carbonatites - if the rock contains >50% modal calcite
  • Melilite-bearing Rocks - if the rock contains >10% modal melilite
  • Kalsilite-bearing Rocks - if the rock contains modal kalsilite
  • Kimberlite - if the rock fits the kimberlite definition (Le Maitre and others, 2002, p.13)
  • Lamproite - if the rock fits the lamproite definition (Le Maitre and others, 2002, p.16)
  • Leucite-bearing Rocks - if the rock contains modal leucite
  • Lamprophyre - if the rock fits the lamprophyre definition (Le Maitre and others, 2002, p.19)
  • Charnokite - if the rock fits the charnokite definition (Le Maitre and others, 2002, p.20)

Definitions for these categories will eventually be added to this website.

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