Types of volcanic rock — Science Learning HubApr 9, 2010 . Rocks are not all the same. Some are heavy, some are light. Others are dark, while some can be almost pure white. Even igneous rocks that.volcanic rock izlivshayasya,volcanic rock izlivshayasya,Igneous Rocks Lesson #12 | Volcano World | Oregon State UniversityWhen most people think about igneous rocks they envision a volcano erupting pumice and lava . The term igneous comes to us from the Latin word "Ignis" which.