Introductory Rock Collection  - Contains  a primary presentation of the three major  rock types. Igneous, sedimentary and Metamorphic. Igneous Rocks : Includes 1. Obsidian 2. Granite   3.Basalt   4. Scoria   5. Rhyolite. Sedimentary Rocks :   Includes 6. Shale 7. Breccia  8. Sandstone                    9. Conglomerate  10. Limestone.  Metamorphic Rocks :  11. Slate  12. Marble 13. Quartzite 14. Gneiss   15. Schist.