Examples of intrusive igneous rocks are diorite, gabbro, granite, pegmatite, and peridotite. Extrusive igneous rocks erupt onto the surface, where they cool quickly to form small crystals. ... These rocks include andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff
Clastic sedimentary rocks such as breccia, conglomerate, sandstone, siltstone, andshale are formed from mechanical weathering debris. Chemical sedimentary rocks, such as rock salt, iron ore, chert, flint, some dolomites, and some limestones, form when dissolved materials precipitate from solution.
Definition of limestone. : a rock that is formed chiefly by accumulation of organic remains (such as shells or coral), consists mainly of calcium carbonate, is extensively used in building, and yields lime when burned