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Abstract: In order to address diamond formation and origin in the lithospheric mantle underlying the Central Slave Craton, we report N- and C-stable isotopic compositions and N-contents and aggregation states for 85 diamonds of known paragenesis (73 peridotitic, 8 eclogitic and 4 from lower mantle) from the Panda kimberlite (Ekati Mine, Lac de Gras Area, Canada). For 12 peridotitic and two eclogitic sulfide inclusion-bearing diamonds from this sample set, we also report multiple-sulfur isotope ratios. The 73 peridotitic diamonds have a mean δ 13C-value of −5.2‰ and range from −6.9 to −3.0‰, with one extreme value at −14.1‰. The associated δ 15N-values range from −17.0 to +8.5‰ with a mean value of −4.0‰. N-contents range from 0 to 1280ppm. The 8 eclogitic diamonds have δ 13C-values ranging from −11.2 to −4.4‰ with one extreme value at −19.4‰. Their δ 15N ranges from −2.1 to +7.9‰ and N-contents fall between 0 and 3452ppm. Four diamonds with an inferred lower mantle origin are all Type II (i.e. nitrogen-free) and have a narrow range of δ 13C values, between −4.5 and −3.5‰. The δ 34S of the 14 analyzed peridotitic and eclogitic sulfide inclusions ranges from −3.5 to +5.7‰. None of them provide evidence for anomalous δ 33S-values; observed variations in δ 33S are from +0.19 to −0.33‰, i.e. within the 2 sigma uncertainties of mantle sulfur (δ 33S=0‰). At Panda, the N contents and the δ 13C of sulfide-bearing peridotitic diamonds show narrower ranges than silicate-bearing peridotitic diamonds. This evidence supports the earlier suggestion established from eclogitic diamonds from the Kaapvaal that sulfide-(±silicate) bearing diamonds sample a more restricted portion of sublithospheric mantle than silicate-(no sulfide) bearing diamonds. Our findings at Panda suggest that sulfide-bearing diamonds should be considered as a specific diamond population on a global-scale. Based on our study of δ 34S, Δ33S, δ 15N and δ 13C, we find no evidence for subduction-related isotopic signatures in the mantle sampled by Panda diamonds. [Copyright &y& Elsevier]