Search for free courses, interactives, videos and more! Free Learning from The Open University. Featured content. Free courses. All content. Diorite Updated Thursday, 28th September A brief description of the nature of diorite. Mostly it looks like dark coloured granite. Copyright: The Open University How was it formed? Get closer to geology. Geology toolkit 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.
Take part now Geology toolkit. Activity Level: 1 Introductory. Copyright information. Publication details Originally published : Wednesday, 27th September Last updated on : Thursday, 28th September Be the first to post a comment Leave a comment.
Diorite is a tough rock, making it difficult to carve and work with. It is so hard that ancient civilizations such as Ancient Egypt used diorite balls to work granite. However, its hardness also allows it to be worked finely and take a high polish and provide a durable finished work. One comparatively frequent use of diorite was for inscription, as it is easier to carve in relief than in three-dimensional statuary. Perhaps the most famous diorite work extant is the Code of Hammurabi , inscribed upon a 2.
It was so valued in early times that the first great Mesopotamian empire—the Empire of Sargon of Akkad —listed the taking of diorite as a purpose of military expeditions. Although one can find diorite art from later periods, it became more popular as a structural stone and was frequently used as pavement due to its durability.
Diorite was used by both the Inca and Mayan civilizations, but mostly for fortress walls, weaponry, etc.
It was especially popular with medieval Islamic builders. In later times, diorite was commonly used as cobblestone; today, many diorite cobblestone streets can be found in England, Guernsey, and Scotland and scattered throughout the world in such places as Ecuador and China.
Although diorite is rough-textured, its ability to take a polish can be seen in the diorite steps of St. Paul's Cathedral , London, where centuries of foot traffic have polished the steps to a sheen. Template:Igneous rocks.
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. It has been given the name "pink marshmallow stone. Find Other Topics on Geology. Maps Volcanoes World Maps. Hardness Picks. Rock, Mineral and Fossil Collections.
Flint, Chert, and Jasper. Tumbled Stones. Fluorescent Minerals.
0コメント