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SOUTH AFRICAN GEOLOGY
| Acid with Quartz. | Intermediate. | Basic, with Iron Ores. | Ultra-basic. | ||
|---|---|---|---|---|---|
| Potash Felspar. | Lime-soda Felspar. | ||||
| Plutonic (large crystals). | Granite. | Syenite. | Diorite. | Gabbro (norite). | Meteorites. |
| Dyke (small crystals). | Quartz-porphyry | Felspar-porphyry | Porphyrite. | Dolerite (diabase, altered dolerite). | — |
| Volcanic (with uncrystallized glass). | Rhyolite (obsidian and pumice) | Trachyte. | Andesite. | Basalt (melaphyre, altered basalt). | Melilite Basalt, (Kimberley blue ground, altered melilite basalt). |
