| An examination of the stones which fell at Fort de France showed them to be of a variety of lava called hornblende and andesite. |
| Small lithic fragments comprise quartzite, gneiss and ubiquitous andesite. |
| Peck used locally quarried andesite, a brittle stone that fractures into sharp, angular shapes and has a sparkly surface. |
| Some rocks have basaltic compositions similar to the well-studied meteorites thought to have come from Mars, but other rocks are more like the volcanic rock andesite. |
| The volcanic strata consist of sheet-like flows of andesite, dacite, basalts, and trachybasalts that are interbedded with agglomerates and tuffs. |
| The fault places massive fractured greenstones over relatively undeformed feldspar andesite porphyry. |
