Diamonds originate in the Earth’s mantle and are brought to the surface by deep-mantle magmas, kimberlites and lamproites. Most diamonds found in kimberlites show complex patterns of growth and dissolution (resorption) surface features. Even a population of diamonds recovered from the same kimberlite body contains large diversity of diamond surface forms, some of which are a result of diamond interaction with the kimberlite magma and others are inherited from the mantle.
Diamonds undergo partial dissolution (resorption) during their residence in the mantle and during the ascent to the Earth’s surface in mantle magmas. Resorption features developed on diamond surface during dissolution provide a record of the conditions both in the mantle source of diamonds and crystallization conditions of kimberlites.
Diamonds undergo partial dissolution (resorption) during their residence in the mantle and during the ascent to the Earth’s surface in mantle magmas. Resorption features developed on diamond surface during dissolution provide a record of the conditions both in the mantle source of diamonds and crystallization conditions of kimberlites.
Diamond Resorption in kimberlite magma produces a number of different surfaces features. A fluid-rich kimberlite magma forming pyroclastic rock via explosive eruption leaves low-relief features on diamonds. Fluid-poor kimberlite magma forming coherent kimberlite facies leaves intense etching on diamond surface. It can form corrosive sculptures or sharp pointy features depending on the composition of kimberlite melt and content of fluid. These resorption types show association with certain kimberlite Classes.
Low-relief and frosted resorption on diamonds from pyroclastic and volcaniclastic kimberlite
Shallow depressions on diamonds from transitional volcaniclastic to hypabyssal kimberlite
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Sharp pointy resorption features on diamonds from coherent kimberlite
Corrosion sculptures on diamonds from hypabyssal kimberlite
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Diamond resorption in the mantle
Diamonds protected by mantle xenoliths during ascent in kimberlite magma can preserve all or some of the features inherited from the mantle. These include both growth and resorption features. There is a number of resorption styles that represent diamond-destructive metasomatic events in the mantle.
Diamonds protected by mantle xenoliths during ascent in kimberlite magma can preserve all or some of the features inherited from the mantle. These include both growth and resorption features. There is a number of resorption styles that represent diamond-destructive metasomatic events in the mantle.
