Pictures of Metamorphic RocksPhotos of Common Foliated and Non-Foliated Metamorphic Rock TypesArticle by: Hobart M. King, PhD, RPGAmphibolite is a non-foliated metamorphic rock that forms through recrystallization under conditions of high viscosity and directed pressure. It is composed primarily of ...
Its abundant mica grains and its schistosity make it a rock of low physical strength, usually unsuitable for use as a construction aggregate, building stone, or decorative stone. The only exception is for its use as a fill when the physical properties of the material are not critical. Schist...
This type of metamorphic rock consists of recrystallized calcite (in limestone) or dolomite (in dolomite rock). In this hand specimen of Vermont marble, the crystals are small. For fine marble of the sort used in buildings and sculpture, the crystals are even smaller. The color of marble can...
Phyllite was originally a fine-grained sedimentary rock such as shale or mudstone, composed mainly of clay minerals in a semi-random orientation. The rock was then buried and subjected to enough directed pressure to move the clay mineral grains towards parallel alignment, and enough heat and chemi...
These pieces of rough average about 1 inch across and were sold for making tumbled stones in a rock tumbler. Much of the "aventurine" sold for lapidary use is actually quartzite. Often it exhibits no aventurescence. Hammer With Caution ! Wise geologists, who have memorable experiences with ...
Rock & Mineral Kits: Get a rock, mineral, or fossil kit to learn more about Earth materials. The best way to learn about rocks is to have specimens available for testing and examination. Gneiss in the Classroom Small rock and mineral specimens about one inch in size are usually adequate ...
Hornfels is a fine-grained metamorphic rock that was subjected to the heat of contact metamorphism at a shallow depth. It was "baked" by heat conducted from a nearby magma chamber, sill, dike, or lava flow. Common temperatures for the formation of hornfels range from about 1300 to 1450 ...
Slate is a fine-grained, foliated metamorphic rock that is created by the alteration of shale or mudstone by low-grade regional metamorphism. The specimen shown above is about two inches (five centimeters) across. ADVERTISEMENT What is Slate? Slate is a fine-grained, foliated metamorphic rock ...
Rock & Mineral Kits: Get a rock, mineral, or fossil kit to learn more about Earth materials. The best way to learn about rocks is to have specimens available for testing and examination. Color: Marble is usually a light-colored rock. When it is formed from a limestone with very few imp...