Robuta

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https://geology.com/rocks/diabase.shtml Diabase: A dark-colored, fine-grained intrusive igneous rock Diabase is an intrusive igneous rock of basaltic composition. It has been used as a construction stone for thousands of years. Its most famous use is in the... dark coloredfine grainedintrusive igneousrock https://geology.com/rocks/scoria.shtml Scoria: Igneous Rock - Pictures, Definition & More Scoria is a dark colored, extrusive igneous rock with a vesicular texture. igneous rock picturesscoriadefinition https://geology.com/rocks/obsidian.shtml Obsidian: Igneous Rock - Pictures, Uses, Properties Obsidian is an igneous rock, a volcanic glass used for thousands of years to make cutting tools. igneous rock picturesuses propertiesobsidian https://geology.com/rocks/gabbro.shtml Gabbro: Igneous Rock - Pictures, Definition & More Gabbro is an intrusive igneous rock that is black in color and has a composition similar to basalt. igneous rock picturesdefinition https://geology.com/rocks/pumice.shtml Pumice: Igneous Rock - Pictures, Definition & More Pumice is an extrusive igneous rock with a vesicular texture and very low specific gravity. It is used to make lightweight concrete, abrasive products and more. igneous rock picturespumicedefinition https://geology.com/rocks/tuff.shtml Tuff - an igneous rock of explosive volcanic eruptions. Tuff is an extrusive igneous rock that forms from the tephra ejected during explosive volcanic eruptions. igneous rockvolcanic eruptionstuffexplosive https://geology.com/rocks/dacite.shtml Dacite: An extrusive igneous rock of the continental crust. Dacite is a fine-grained igneous rock found on the continental crust above subduction zones where a relatively young oceanic plate has melted below. igneous rockcontinentalcrust https://geology.com/rocks/andesite.shtml Andesite: Igneous Rock - Pictures, Definition & More Andesite is an extrusive igneous rock with a mineral composition between granite and basalt. It is named after the Andes Mountains, where it is very abundant. igneous rock picturesdefinition https://geology.com/rocks/diorite.shtml Diorite: Igneous Rock - Pictures, Definition & More Diorite is an intrusive igneous rock of intermediate composition. igneous rock picturesdefinition https://geology.com/rocks/granite.shtml Granite: Igneous Rock - Pictures, Definition & More Granite is the most widely known igneous rock. It is an intrusive rock with visible grains of feldspar, quartz, mica, and amphibole minerals. It is durable and... igneous rock picturesgranitedefinition