Diamonds from the Nassau Mountains, Suriname

Diamonds have been found in Suriname since the late 19th century, primarily in alluvial deposits in the Marowijne greenstone belt in the Guiana Shield:

• Location: The diamonds are found in the Paramaka Creek area of the Nassau Mountains, a horseshoe-shaped range in northeastern Suriname.
• Characteristics: The diamonds are primarily type IaAB, with nitrogen as both A and B aggregates. They have a variety of colors, including colorless, brown, and slightly greenish, and some have green or brown irradiation spots.
• Mineral inclusions: The diamonds contain mineral inclusions of forsterite and enstatite, which indicate a peridotitic paragenesis.
• Surface features: The diamonds show evidence of late-stage resorption, which occurred during their transport to the earth’s surface.
• Luminescence: Most samples display blue and/or green luminescence.
• Growth patterns: The diamonds have concentric growth patterns. 

The Marowijne greenstone belt is part of a 1,500-km-long granite-greenstone terrane that extends from Venezuela to Brazil. It formed about 2,180–1,950 million years ago when the Amazonian and West African cratons collided