|Latitude & Longitude (WGS84):||18° 34' 36'' South , 47° 52' 36'' West|
|Latitude & Longitude (decimal):||-18.57694,-47.87667|
|Köppen climate type:||Aw : Tropical savanna, wet|
Cascalho Rico means “rich gravel.” This label leaves little doubt that alluvial diamonds were found in stream systems that flow northward from the Cretaceous chapada (plateau) to the south, past the town of Cascalho Rico. The most important stream system in the area is that of the Córrego dos Pedras (“stream of rocks,” córrego referring to a smaller stream than a river, such as a creek). This diamond-bearing drainage would be the farthest west of any in the Coromandel District. Information to confirm that diamonds have been here is difficult to find, but Fleischer (1998) claimed that a lineation trending northwestward from Iraí de Minas and through Romaria extends as far as Cascalho Rico. Fleischer postulated that this lineation corresponds to the position of a normal fault and associated graben in which the diamondiferous conglomerate was deposited at Romaria, and implied that a similar diamond-bearing conglomerate occurs at Cascalho Rico. Additional study is needed to verify these ideas, but the name of the town “says it all.” Coordinates for this locality correspond to the townsite, although the entire Córrego dos Pedras drainage basin is likely prospective. Directly across the drainage divide to the east is the Rio Bagagem drainage system, where the Estrela do Sul (“Star of the South”) diamond was discovered in 1853, igniting a rush of diamond miners to this region of Minas Gerais.
NK, rev. May 2018
1 valid mineral.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
|Neoproterozoic - Paleoproterozoic|
541 - 2500 Ma
|Proterozoic crystalline metamorphic rocks|
Age: Proterozoic (541 - 2500 Ma)
Lithology: Low-medium grade unclassified metamorphic rock
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529.