Posted on | May 6, 2011 | Comments Off on New Mineral, Krotite, Named After Mānoa Researcher
The first natural occurrence of a low-pressure CaAl2O4 mineral has been found in a refractory inclusion in a carbonaceous chondrite meteorite. The new mineral Ca1.02Al1.99O4 is now officially approved by the Commission on New Minerals, Nomenclature and Classification of the International Mineralogical Association as krotite. The mineral’s name honors Alexander N. Krot, a Mānoa researcher known for his achievements in meteoritics, especially for studies of the formation of calcium-aluminum-rich inclusions (CAIs) and chondrules, and his significant contributions to the understanding of early solar system processes.
Krotite is the dominant mineral in the central and mantle areas of an unusual CAI in the NWA 1934 carbonaceous chondrite. The 2.75 mm x 4.5 mm inclusion is composed mainly of aggregates of krotite crystals, with a few other calcium-aluminum or magnesium-aluminum oxides and a few silicates in a thin rim of concentric layers. Cracks, mainly filled with iron and aluminum hydroxides, crosscut the CAI’s rim and parts of its interior giving it a cracked egg appearance. The CAI itself is surrounded by a matrix of mostly fine-grained olivine.
This CAI, along with its new mineral, krotite, will be the subject of additional research to determine formation and cosmochemical details. Because CAIs were the first solids formed in the solar nebula about 4.6 billion years ago, they help cosmochemists piece together records of nebular and early solar system processes and how the first solid building blocks eventually turned into asteroids and planets.