Igneous Rocks - Geology (U.S. National Park Service)
Igneous rocks are classified both by their chemical composition, mineral composition, texture, and structure. Texture and structure refer to the relationships between crystals, groundmass, vesicles, and other components of a rock. Igneous rocks are mostly made of the most common elements found in the Earth’s crust. In descending order, they are:
Virtual Collection: Rocks - Earth@Home
The Virtual Collection of Rocks is arranged according to standard classification schemes taught in most introductory-level Earth science courses. Collections of interactive 3D models of representative samples from each of the major rock groups may be accessed below.
COLLECTING ROCKS - USGS Publications Warehouse
Geologists classify rocks in three groups, according to the major Earth processes that formed them. The three rock groups are igneous, sedimentary, and metamorphic rocks. Anyone who wishes to collect rocks should become familiar with the characteristics of these three rock groups.
Rocks - Natural History Museum
The Museum rock collection contains approximately 123,000 sedimentary, igneous and metamorphic rocks collected around the world during the past 250 years. These specimens help us better understand the evolution of our planet.
Igneous Rocks - A 3D model collection by Museum of
Igneous rocks form by the cooling and crystallization of hot, molten rock (magma & lava). If this happens at or near the land surface, or on the seafloor, they are extrusive (or volcanic) igneous rocks. If this happens deep underground, they are intrusive (or plutonic) igneous rocks.
Igneous rock - Wikipedia
Igneous rock (igneous from Latin igneus 'fiery'), or magmatic rock, is one of the three main rock types, the others being sedimentary and metamorphic. Igneous rocks are formed through the cooling and solidification of magma or lava. The magma can be derived from partial melts of existing rocks in either a planet's mantle or crust.
Rock Collection | Department of Earth and Planetary Sciences
The EPS Rock Collection contains over 10,000 samples and is housed in rooms 314d and 312 of the Harvard Science Center. The collection consists of the following: Igneous, Metamorphic, and Sedimentary Rock Collection
Rocks: Igneous, Metamorphic and Sedimentary - Geology.com
Rocks hold the history of the earth and the materials that will be used to build its future. Igneous Rocks: Photos, descriptions and facts about intrusive and extrusive igneous rocks. Metamorphic Rocks: Photos, descriptions and facts about foliated and non-foliated metamorphic rocks.
Rock Kit | Rock Collection | Rock Collecting - Geology.com
A comprehensive collection of 36 different sedimentary, metamorphic and igneous rocks. Includes the specimens most often described in geology textbooks. Larger specimens than in the Rock Study Kit described above - they measure between 1 and 1.5 inches in diameter.
Igneous Rocks | Pictures of Intrusive and Extrusive Rock Types
Intrusive igneous rocks crystallize below Earth's surface, and the slow cooling that occurs there allows large crystals to form. Examples of intrusive igneous rocks are: diabase , diorite , gabbro , granite , pegmatite , and peridotite .