Characteristics of Nitrogen and Other Impurities in Diamond, as Revealed by Infrared Absorption Data

Abstract

Diamond crystals from Siberian, Arkhangelsk, South African, Canadian and South American deposits were analyzed for structurally bound nitrogen, hydrogen and "platelet" defects using infrared (IR) absorption spectroscopy. Wide variations in total nitrogen and hydrogen contents and in the state of nitrogen aggregation were established in diamond crystals from different areas and deposits. On this basis, three groups were distinguished: (1) low-nitrogen, highly-aggregated-nitrogen diamond, (2) intermediate diamond crystals, and (3) high-nitrogen, poorly-aggregated-nitrogen diamond (occasionally with high concentrations of hydrogen and "platelets"). They represent, in general terms, three major stages of diamond formation: (1) the initial stage at high P-T conditions, which occasionally occurs in super-deep areas (e.g., lower mantle and transition zone), (2) the main stage, and (3) the final stage, which represents the latest episodes of magmatic evolution and is characterized by high oversaturation of the crystallization medium and high internal temperature-gradients. These data may be used for "fingerprinting" of diamond, in prospecting for new deposits in diamondiferous areas, and in the evaluation of diamond crystals from newly discovered deposits.

Diamond From the Los Coquitos Area, Bolivar State, Venezuela

“…Errors on the concentrations determined were less than 20%. One can fi nd the principles that were used for interpretation of IR analysis of diamond in Kaminsky et al (2000Kaminsky et al ( , 2001b, Kaminsky & Khachatryan (2001, and Khachatryan & Kaminsky (2003). Isotope analyses were performed by K. Maltsev (GEOHI, Russia) using samples from 2 to 15 mg in weight with the VARIAN-MAT-230 mass spectrometer; this was done with an accuracy of <0.1‰ PDB ( 13 C/ 12 C PDB = 0.0112372).…”

“…Diagram after Kaminsky & Khachatryan (2001). placer. This difference may point to dissimilar thermal and kinetic parameters during the formation of the two groups of diamond.…”

The influence of defect levels on the dose rate dependence of synthetic diamond detectors of various types on exposures to high-energy radiotherapy beams

“…As established by Nam et al (1991) N s (which is dominant in synthetic diamond) is responsible for many performance characteristics of diamond radiation detectors. Whereas ESR is a useful and non-destructive technique for the characterisation of the concentration of N s ([N s ]), UV absorption can be used to identify diamonds with N complexes (Nam et al, 1991;Davies, 1999) while IR spectroscopy provides a means for the identification of aggregate N in diamond and perhaps the estimation of their concentration (Kaminsky and Khachatryan, 2001). Presented in Table 1 are values of the [N s ] for the diamond crystals as determined by ESR.…”

Mineralogy of diamonds from the Ozernaya pipe, Ottorzhenets body, Pervomaiskaya and Novogodnyaya veins, Yakutia

“…The extremely low concentration of nitrogen impurity as B 1 and B 2 centers differs diamonds from the Ozernaya pipe from diamonds in the Yubileinaya pipe and other deposits of the Daldyn-Alakit diamond-bearing district (Kaminsky et al, 1988;Sobolev and Lisoivan, 1978;Kaminsky and Khachatryan, 2001). The B 1 center concentration in most diamonds (approximately 2/3 of the examined crystals) ranges from 0.25 to 1.75 × 10 19 cm -3 and the distribution pattern is a straight line gently sloping to the right.…”