Why is diorite igneous

In areas where diorite occurs near the surface, it is sometimes mined for use as a crushed stone. It has a durability that compares favorably to granite and trap rock. It is used as a base material in the construction of roads, buildings, and parking areas. It is also used as a drainage stone and for erosion control. In the dimension stone industry, diorite is often cut into facing stone, tile, ashlars, blocking, pavers, curbing, and a variety of dimension stone products.

These are used as construction stone, or polished and used as architectural stone. Diorite was used as a structural stone by the Inca and Mayan civilizations of South America and by many ancient civilizations in the Middle East. In the dimension stone industry, diorite is sold as a " granite. This simplifies discussions with customers who do not know how to identify igneous and metamorphic rocks. Diorite Sculptures: The sculpture on the left is a diorite statue of Gudea, a Mesopotamian ruler, made in about BC.

It is about 19 inches tall and is currently displayed at the Metropolitan Museum of Art. A public domain image. The vase on the right was made in ancient Egypt from diorite with spectacular feldspar phenocrysts. It is in the collection of the Field Museum. Diorite is difficult to sculpt because of its hardness, variable composition, and coarse grain size. For those reasons, it is not a favored stone of sculptors, although it was popular among ancient sculptors of the Middle East.

The most famous diorite sculpture is the Code of Hammurabi, a black diorite pillar about seven feet tall, inscribed with Babylonian laws in about BC. Diorite has the ability to accept a bright polish, and it has occasionally been cut into cabochons or used as a gemstone. In Australia, a diorite with beautiful pink feldspar phenocrysts has been cut into cabochons and called "pink marshmallow stone. The best way to learn about rocks is to have specimens available for testing and examination.

Diorite Cabochon: A diorite in Australia contains large, beautiful pink feldspar crystals. It is often cut into cabochons for use as a novelty gem. The basic classification is the same as for plutonic rocks: with increasing silica content, they include: basalt, andesites, dacites, rhyolite, pumice and obsidian. Main types of igneous rocks The most widely used and simplest classification of igneous rocks is according to the silica SiO 2 content in the bulk rock composition. Wikimedia Commons.

Diorite sample image: Michael C. Rygel via Wikimedia Commons. Andesite Andesite from Methana, Greece. Montrer plus. Android Version iOS. Diorite forms from magma that does not contain a lot of quartz silica or the light coloured minerals that make up granite. Discover the unique landscape of the British Isles with our interactive Geology Toolkit, featuring a geology timeline, rock analyser, rock cycle, landscape features and safety tips.

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