Alluvial diamonds have been found in Suriname since the late 19th century, but to date the details of their origin remain unclear. Here we describe diamonds from Paramaka Creek (Nassau Mountains area) in the Marowijne greenstone belt, Guiana Shield, north-eastern Suriname. Thirteen samples were studied, consisting mainly of euhedral crystals with dominant octahedral and dodecahedral habits. They had colourless to brown to slightly greenish body colours, and some showed green or (less commonly) brown irradiation spots. Surface features showed evidence of late-stage resorption that occurred during their transport to the earth's surface. The studied diamonds were predominantly type IaAB, with nitrogen as both A and B aggregates. In the DiamondView most samples displayed blue and/or green luminescence and concentric growth patterns. Their mineral inclusion assemblages (forsterite and enstatite) indicate a peridotitic (possibly harzburgitic) paragenesis.

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The Armina Formation along the Coppename River is a part of the 2.26-2.10 Ga Paleoproterozoic Marowijne Greenstone Belt of Suriname. It is in faulted contact with the 2.08-2.05 Ga Bakhuis Granulite Belt. This paper studies the relation between these units based on field observations, petrographic, geochemical and age data. The metaturbidites show a volcanic arc-type setting in the north, and a continental arc setting in the south. No traces of any Bakhuis provenance could be demonstrated in the metaturbidites. Detrital zircons from the Armina metaturbidites show ages around 2162 ± 30 Ma, which is similar to the age of Armina Formation detrital zircons elsewhere in northern Suriname. As Bakhuis sillimanite gneisses also show inherited zircons between 2120 and 2150 Ma, the Bakhuis granulites and Armina metaturbidites protoliths might be coeval and share a common provenance area. Younger granites intruding the Armina metaturbidites show ages of 2005 (Voltzberg), 2004 (Raleigh Falls) and 1990 Ma (Vankaaikisula), slightly higher than most Wonotobo granites in western Suriname.@en