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False-color scanning electron microscope image of kimberlite from South Africa. Olivine crystals (green) are in a fine-grained matrix made up of clay minerals and carbonates (presented in blue, purple and buff colors). Kimberlite is an igneous rock and a rare variant of peridotite. It is most commonly known to be the main host matrix for diamonds.
Lamproite pipes operate similarly to kimberlite pipes, except that the boiling water and volatile compounds contained in the magma act corrosively on the overlying rock, resulting in a broader cone of eviscerated rock (the ejection of this rock also forms a tuff ring, like kimberlite eruptions). This broad cone is then filled with volcanic ash ...
The ML pipes form part of the Northern Alberta kimberlite province, along with the nearby Birch Mountains kimberlite field and the Buffalo Head Hills kimberlite field.They were discovered in 1989-90 just north of Mountain Lake (55.456291n 117.714510w), which lies about 75 km (47 mi) northeast of Grande Prairie, Alberta.
The ML rocks are not considered to be archetypal kimberilte and have been variously classified as alkaline ultramafic rocks, hybrid alkaline ultramafic rocks, alkali olivine basalt and basanite; they are difficult to classify because of strong clay alteration that has obliterated most of their original mineralogy.
The lake Ellen Kimberlite is popular with rock hounds as the classic indicator minerals (pyrope, magnesian ilmenite and chrome diopside) for kimberlite are easily found in the material, though few are of gem quality and size. While there was considerable interest in diamond exploration in Michigan's Upper Peninsula and northern Wisconsin for ...
Research at Argyle diamond have shown that most stones are of E-type; they originate from eclogite source rocks and were formed under high temperature ~1,400 °C (2,600 °F). The Argyle diamond mine is the main source of rare pink diamonds. Olivine lamproite pyroclastic rocks and dikes are sometimes hosts for diamonds.
The following is a list of rock types recognized by geologists.There is no agreed number of specific types of rock. Any unique combination of chemical composition, mineralogy, grain size, texture, or other distinguishing characteristics can describe a rock type.
Kimberlite: formed in volcanic pipes and at least 35% olivine [9] Kimberlite is a highly brecciated variant of peridotite formed in volcanic pipes and is known for being the host rock to diamonds. Unlike other forms of peridotite, kimberlite is quite rare. [10] Pyroxene peridotite: From 40% to 90% olivine and less than 5% hornblende