Search results
Results from the WOW.Com Content Network
Green quartz is sometimes called green amethyst; the scientific name is prasiolite. [9] Other names for green quartz are vermarine and lime citrine. Amethyst frequently shows color zoning, with the most intense color typically found at the crystal terminations. One of gem cutters' tasks is to make a finished product with even color. Sometimes ...
Mineralogy applies principles of chemistry, geology, physics and materials science to the study of minerals. Mineralogy [n 1] is a subject of geology specializing in the scientific study of the chemistry, crystal structure, and physical (including optical) properties of minerals and mineralized artifacts.
Liesegang rings (/ ˈ l iː z ə ɡ ɑː ŋ /) (also called Liesegangen rings or Liesegang bands) are colored bands of cement observed in sedimentary rocks that typically cut across bedding. [ 1 ] [ 2 ] These secondary ( diagenetic ) sedimentary structures exhibit bands of ( authigenic ) minerals that are arranged in a regular repeating pattern ...
Chromite and magnetite are ore minerals that form in this way. [1] Liquid immiscibility: sulfide ores containing copper, nickel, or platinum may form from this process. As a magma changes, parts of it may separate from the main body of magma. Two liquids that will not mix are called immiscible; oil and water are an example.
Colorless beryls, also called goshenite, become pure yellow when irradiated, which are called golden beryl or heliodor. [1] Quartz crystals turn "smoky" or light gray upon irradiation if they contain an aluminum impurity, or amethyst if small amounts of iron are present in them; either of the results can be obtained from natural radiation as well.
Stony-iron meteorites or siderolites are meteorites that consist of nearly equal parts of meteoric iron and silicates. This distinguishes them from the stony meteorites, that are mostly silicates, and the iron meteorites, that are mostly meteoric iron. [1] Stony-iron meteorites are all differentiated, meaning that they show signs of alteration.
Ironstone (sandstone with iron oxides) from the Mississippian Breathitt Formation, Mile Marker 166, I-64, Kentucky. Ironstone is a sedimentary rock, either deposited directly as a ferruginous sediment or created by chemical replacement, that contains a substantial proportion of an iron ore compound from which iron (Fe) can be smelted commercially.
However, sources do not agree that the yellow-orange quartz component of ametrine may properly be called citrine. Like the purple color of amethyst, the yellow color in ametrine originates from trace amounts of iron in the crystal structure. The difference in coloration is due to the iron existing in different oxidation states. The yellow ...