... is consistent with a 7 Å phase, namely pecoraite or népouite. Relevant chemical features are an exceptionally high Ni/Mg ratio, a significant level of Cu substituting for Ni, and a low content of S, possibly in tetrahedral sites. Olivine and orthopyroxene in the harzburgite host rock are only partially...

... shows Ni-rich serpentine mineral (NiO = 33.4-33.9 wt %, SiO 2 = 37.55-38.96 wt %, MgO= 14.83-16.89 wt %). The composition and X-ray diffraction pattern characterize this Ni-rich serpentine mineral as népouite which is suggested to be a hydrothermal alteration product of NiO-rich olivine in a fore-arc...

...Fabien Baron; Sabine Petit Abstract A series of 1:1 silicate clays of the lizardite-nepouite series [Si 2 Mg 3−x Ni x O 5 (OH 4 ) with x = 0, 0.5, 1, 1.5, 2, 2.5, and 3] was synthesized at 220 °C during 7 days from coprecipitated gels in hydrothermal conditions. A clear relationship was evidenced...

... unit R 3 Si 2 O 5 (OH) 4 are called nepouites, and those with fewer Ni ions are called nickel lizardites. The samples vary considerably in structural order and the nepouites generally are less well-ordered than the nickel lizardites. Among the latter, two show clear evidence for a 2-layer orthogonal...