Lamont meteorite, Lamont, Greenwood Co., Kansas, USA

Latitude & Longitude (WGS84):	38° 4' 40'' North , 96° 1' 35'' West
Latitude & Longitude (decimal):	38.07778,-96.02639
Non-native locality type:	Meteorite
Meteorite Class:	Mesosiderite meteorite
Meteoritical Society Class:	Mesosiderite
Metbull:	View entry in Meteoritical Bulletin Database
Köppen climate type:	Cfa : Humid subtropical climate

Stony-iron, Mesosiderite
Find, 1940; 38.69 kg

Around 1940 a 38.69 kg meteorite was found among stones in a fence row. The discovery, however, was not officially announced until 1997. The meteorite is a somewhat unusual mesosiderite with conspicuous large olivine and pyroxene 'megacrysts' (≤2 cm) as well as the usual melange of brecciated pyroxene, plagioclase, and metal found in all mesosiderites. Irregular olivine crystals are in contact with plagioclase and low-Ca pyroxene. Both olivine and pyroxene crystals are characterised by Mg-rich equilibrated cores with some Fe enrichment at the edges. Small chromites forms necklaces around many of the olivines. Within the matrix abundant plagioclase as well as minor amounts of merrillite and tridymite are notable. The suggestion is that the silicates within Lamont formed as early or earlier than the silicates of other mesosiderites.

Lamont is one of 155 mesosiderites listed at The Meteoritical Society's 'Meteoritical Bulletin Database' (June 2015). Approximately half of the mass was distributed to public scientific institutions: the U.S. Museum of Natural History (~7kg), UCLA (~5 kg) and the Field Museum of Natural History (~4kg). An additional 5.339 kg is also at the Southwest Meteorite Laboratory.

Caveat: While the pyroxenes have been given some very sophisticated state of the art treatment, the meteoritic iron has been virtually ignored in the literature cited by NASA ADS.

Mineral List

8 valid minerals.

Meteorite/Rock Types Recorded

References

External Links