enow.com Web Search

Search results

1. Results from the WOW.Com Content Network

2. Rock (geology) - Wikipedia

   en.wikipedia.org/wiki/Rock_(geology)

   Most rocks contain silicate minerals, compounds that include silica tetrahedra in their crystal lattice, and account for about one-third of all known mineral species and about 95% of the earth's crust. [6] The proportion of silica in rocks and minerals is a major factor in determining their names and properties. [7]

3. List of minerals - Wikipedia

   en.wikipedia.org/wiki/List_of_minerals

   Differences in chemical composition and crystal structure distinguish the various species. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by mineralogists or wider society as a mineral variety. Mineral variety names are listed after the valid minerals for each letter.

4. Petoskey stone - Wikipedia

   en.wikipedia.org/wiki/Petoskey_stone

   A Petoskey stone is a rock and a fossil, often pebble-shaped, that is composed of a fossilized rugose coral, Hexagonaria percarinata. [1] Such stones were formed as a result of glaciation, in which sheets of ice plucked stones from the bedrock, grinding off their rough edges and depositing them in the northwestern (and some in the northeastern) portion of Michigan's lower peninsula.

5. Glossary of geology - Wikipedia

   en.wikipedia.org/wiki/Glossary_of_geology

   Also called Indianite. A mineral from the lime-rich end of the plagioclase group of minerals. Anorthites are usually silicates of calcium and aluminium occurring in some basic igneous rocks, typically those produced by the contact metamorphism of impure calcareous sediments. anticline An arched fold in which the layers usually dip away from the fold axis. Contrast syncline. aphanic Having the ...

6. List of rock types - Wikipedia

   en.wikipedia.org/wiki/List_of_rock_types

   Phosphorite – Sedimentary rock containing large amounts of phosphate minerals – A non-detrital sedimentary rock that contains high amounts of phosphate minerals; Sandstone – Type of sedimentary rock; Shale – Fine-grained, clastic sedimentary rock; Siltstone – Sedimentary rock which has a grain size in the silt range

7. List of gemstones by species - Wikipedia

   en.wikipedia.org/wiki/List_of_gemstones_by_species

   Rock crystal (var.) Shocked quartz (var.) Smoky quartz (var.) Quartzite; R–Z ... Some minerals made into gemstones may display a chatoyancy or cat's eye effect, ...