@article{fdi:010064156,
  title = {{G}eochemical and oxygen isotope signatures of mantle corundum megacrysts from the {M}buji-{M}ayi kimberlite, {D}emocratic {R}epublic of {C}ongo, and the {C}hangle alkali basalt, {C}hina},
  author = {{G}iuliani, {G}aston and {P}ivin, {M}. and {F}allick, {A}. {E}. and {O}hnenstetter, {D}. and {S}ong, {Y}. and {D}emaiffe, {D}.},
  editor = {},
  language = {{ENG}},
  abstract = {{O}xygen isotope signatures of ruby and sapphire megacrysts, combined with trace-element analysis, from the {M}buji-{M}ayi kimberlite, {D}emocratic {R}epublic of {C}ongo, and the {C}hangle alkali basalt, {C}hina, provide clues to specify their origin in the deep {E}arth. {A}t {M}buji-{M}ayi, pink sapphires have 8180 values in the range 4.3 to 5.4 parts per thousand ({N}=10) with a mean of 4.9 +/- 0.4 parts per thousand, and rubies from 5.5 to 5.6 parts per thousand ({N}=3). {T}he {G}a/{M}g ratio of pink sapphires is between 1.9 and 3.9, and in rubies, between 0.6 and 2.6. {T}he blue or yellow sapphires from {C}hangle have delta {O}-18 values from 4.6 to 5.2 parts per thousand, with a mean of 4.9 +/- 0.2 parts per thousand ({N}=9). {T}he {G}a/{M}g ratio is between 5.7 and 11.3. {T}he homogenous isotopic composition of ruby suggests a derivation from upper mantle xenoliths (garnet lherzolite, pyroxenite) or metagabbros and/or lower crustal garnet clinopyroxenite eclogite-type xenoliths included in kimberlites. {D}ata from the pink sapphires from {M}buji-{M}ayi suggest a mantle origin, but different probable protoliths: either subducted oceanic protolith transformed into eclogite with delta {O}-18 values buffered to the mantle value, or clinopyroxenite protoliths in peridotite. {T}he {C}hangle sapphires have a mantle {O}-isotope signature. {T}hey probably formed in syenitic magmas produced by low degree partial melting of a spinel {I}herzolite source. {T}he kimberlite and the alkali basalt acted as gem conveyors from the upper mantle up to the surface.},
  keywords = {{O}xygen isotopes ; {C}hemistry ; {C}orundum ; {K}imberlite ; {A}lkali basalt ; {O}rigin ; {M}antle ; {REPUBLIQUE} {DEMOCRATIQUE} {DU} {CONGO} ; {CHINE}},
  booktitle = {},
  journal = {{C}omptes {R}endus {G}eoscience},
  volume = {347},
  numero = {1},
  pages = {24--34},
  ISSN = {1631-0713},
  year = {2015},
  DOI = {10.1016/j.crte.2014.12.003},
  URL = {https://www.documentation.ird.fr/hor/fdi:010064156},
}