...Peter J. Heaney; Edward P. Vicenzi; Subarnarekha De Abstract Polycrystalline aggregates of diamond called carbonado and framesite have excited the attention of scientists because their crystallization histories are thought to depart markedly from established modes of diamond genesis. In contrast...

...Figure 4 Carbon isotopic signatures for framesite diamonds from Orapa ( Deines et al, 1993 ), Venetia ( Jacob et al., 2000 ) and an unknown South African locality ( Dubosi and Kurat, 2010 ). The Orapa framesites are inclusion free, but the two other populations have websteritic inclusions. ...

...Fig. 2. C and N isotopic composition of carbonado, framesites and yakutites (shock diamonds). Carbonado – filled markers (circles – Brazil, squares – Ubangui); framesites – empty squares; yakutites – empty circles. ...

...Sami Mikhail; Daniel Howell; Francis M. McCubbin Abstract A collection of 35 diamondite samples (polycrystalline diamond aggregates, sometimes referred to as framesites), assumed to be from southern Africa, have been studied to investigate their infrared (IR) spectroscopic characteristics. Due...

... and carbon isotopic signatures. Diamonds with complex growth zones and deformation textures can be explained in terms of dynamic mantle processes, linked to formation of the sheared peridotites, within the thermal aureole surrounding the kimberlite magma in which the megacryst suite crystallised. Framesites...

...Dorrit E. Jacob; Sami Mikhail Nothing better serves to illuminate the blurred line between academia and industry in diamond science than the diversity of, and etymology behind, the nomenclature applied to polycrystalline diamond. The most commonly used names are framesite, stewartite, diamondite...

... Earth, recycled crustal sources, and crystallization processes. Two lesser known and understood varieties of diamond are, first, natural polycrystalline diamond—carbonado and framesite—and, second, microdiamonds discovered over the last 20 years associated with metamorphic rocks. Heaney, Vicenzi...

... aggregates (framesites). Thus, the picrochromite is a signature indicative of its U/P-type (ultramafic) diamond environment. The only other reported occurrence of eskolaite to date is from the Zagadochnaya kimberlite in Yakutia, where it coexists with a set of eclogitic (E-type) Cr-enriched minerals...

..., irregularly shaped, polycrystalline aggregates with grain sizes ranging from less than 1 to several hundred μm ( Dismukes et al. 1988 ; Jeynes 1978 ; Trueb and de Wys 1971 ). Unlike non-porous microcrystalline diamond aggregates found in kimberlites (e.g., stewartite and framesite), carbonado is recovered...

... , 1998) and Corte et al . (1998) are plotted. Nitrogen concentrations in carbonado are higher than in impact-generated diamond, and lower than in cubic and metamorphic diamond. “Framesites” have similar nitrogen concentration to carbonado. ...

... ) localities, respectively. Note that three samples belong to typical polycristalline aggregates (framesites) reported from many kimberlite pipes ( Kirkley et al., 1994 ; Orlov, 1973 ; Sobolev, 1974 ). Garnets have compositions typical of eclogitic diamonds ( Fig. 8 ), corresponding to group B...

... adjacent at times in the Archean, suggests that they may all have been created in a single event ( Heaney et al., 2005 ), although they are in some respects similar to other polymineralic diamond varieties such as framesites and yakutites ( McCall, 2009 ). Carbonado is set apart from other diamond...

... objective. Probably, the unusual smooth surface of the carbonado specimens can serve as a good discriminating criterion. Based on comprehensive isotopic analyses it was suggested ( Burgess et al. , 1998 ) that carbonado might be “an old framesite”, i.e. “common” polycrystalline diamond which underwent...