... ; Katayama et al., 2001 ; Katayama and Maruyama, 2009 ; Ragozin et al., 2009 ; Stepanov et al., 2016 ; Rezvukhina et al., 2020 ). The most unusual diamondiferous metamorphic rocks of the Kumdy-Kol microdiamond deposit are garnet–pyroxene rocks occurring as boudines and interlayers in garnet–biotite...

... of the fluids related to UHPM diamond formation while the carbon isotope ratios of the diamond itself can inform us about the source of carbon. The purpose of this review is to provide a brief history on the discovery of microdiamonds starting with work that began in the mid-1960s in Kokchetav massif...

...-rich silica glass (former melt) inclusions in microdiamond from the gneisses of Kokchetav and Erzgebirge massifs: Diversified characteristics of the formation media of metamorphic microdiamond in UHP rocks due to host-rock buffering . Earth Planet. Sci. Lett. 243 , 94 – 106 , doi: 10.1016/j . epsl...

... that partially overlaps with the data of Perraki et al. ( 2009 ). Compared to possibly radiation-damaged microdiamond inclusions in zircon cores from tourmaline-rich quartzofeldspathic rock (Shimizu and Ogasawara, 2014 ), the main Raman peak of the diamonds examined here is generally shifted to higher...

..., obtained on the two reference samples, demonstrate that precision was less than 0.2‰. The diamond grains are 0.06–0.7 mm in size (i.e., they may be called microdiamonds) and are colorless to yellow-green in color ( Fig. 4 ). They are accompanied, in samples, with single grains of moissanite...

...Katarzyna Walczak; Simon Cuthbert; Ellen Kooijman; Jarosław Majka; Matthijs A. Smit Abstract The first find of microdiamond in the Nordøyane ultra-high-pressure (UHP) domain of the Western Gneiss Region (WGR) of the Scandinavian Caledonides reshaped tectonic models for the region. Nevertheless...

.... , Wang , W. , 2017 . Spectroscopic analysis of microdiamonds in ophiolitic chromitite and peridotite . Lithosphere 10 ( 1 ), 133 – 141 . Moraes , L.I. , 1934 . Depositos diamantiferous no norte do estado de Minas Geraes. Bol . Servico...

... and microdiamond have been found. In ZSZ serpentinites, the new UHP assemblage predates the previously recognized HP-UHP paragenesis, which was recently dated at 65 Ma. This finding opens up a new interpretation for the petrologically and structurally well-constrained HP/UHP records, especially because all other...

...Xiangzhen Xu; Pierre Cartigny; Jingsui Yang; Yildirim Dilek; Fahui Xiong; Guolin Guo Abstract We report new δ 13 C data and N content and aggregation state values for microdiamonds recovered from peridotites and chromitites of the Luobusa ophiolite (Tibet) and chromitites of the Ray-Iz ophiolite...

...Kyaw Soe Moe; Jing-Sui Yang; Paul Johnson; Xiangzhen Xu; Wuyi Wang Abstract Microdiamonds ∼200 µm in size, occurring in ophiolitic chromitites and peridotites, have been reported in recent years. Owing to their unusual geological formation, there are several debates about their origin. We studied...

... greater than 200 km . Nature , 407 , 734 – 736 . One example is from UHP microdiamond-bearing quartzofeldspathic lenses of “saidenbachite” in the gneiss-eclogite unit of the Saxonian Erzgebirge (Bohemian Massif) adjacent to the Saidenbach reservoir (Germany; 56.220° N, 45.886° E; e.g...

... in ultrahigh-pressure quartzofeldspathic gneisses of the Kumdy-Kol area of the Kokchetav Massif, northern Kazakhstan. Maruyamaite contains inclusions of microdiamonds, and probably crystallized near the peak pressure conditions of UHP metamorphism in the stability field of diamond. Crystals occur as anhedral...

... , M.A. , 1991 . New occurrence of microdiamonds in metamorphic rocks as proof for regional ultrahigh-pressure metamorphism in the Kokchetav massif . Dokl. Akad. Nauk SSSR 321 ( 1 ), 189 – 193 . Shatsky , V.S. , Jagoutz , E. , Kozmenko , O.A...

..., 1995 ; Dobretsov, 2003 , 2010 , 2011 ; Dobretsov and Buslov, 2004 , 2007 , 2011 ; Dobretsov et al., 1995a , b , c ; Ernst and Liou, 2008 ; Ernst et al., 1995 , 2007 ; Korobkin and Smirnov, 2006 ). The presence of microdiamond inclusions in garnet, pyroxene, and zircon from garnet–pyroxene...

..., electron probe microanalysis, and transmission/analytical electron microscopy. The obtained results confirmed the presence of microdiamonds and indicative signs of ultrahigh pressures (K in clinopyroxene) for seven of the eight previously recognized layers of the sample. Only one layer (3) containing...

... are known from several occurrences worldwide. We report on the discovery of microdiamond in kyanite-garnet gneiss from allochthonous metasediments of the Seve Nappe Complex in the Scandinavian Caledonides. Our discovery calls for general reconsideration of existing exhumation models of deeply subducted...

... that kumdykolite contains 2 wt% CaO, probably indicating significant miscibility with the Ca-end-member svyatoslavite. Similar to the case of microdiamond inclusions, the kumdykolite-bearing multiphase inclusion is located in the Ca- and Mg-rich central part of the garnet and thus must have been trapped at P...