Transjordanite, Ni2P, a new terrestrial and meteoritic phosphide, and natural solid solutions barringerite-transjordanite (hexagonal Fe2P–Ni2P)

Abstract

This paper is a first detailed report of natural hexagonal solid solutions along the join Fe2P–Ni2P. Transjordanite, Ni2P, a Ni-dominant counterpart of barringerite (a low-pressure polymorph of Fe2P), is a new mineral. It was discovered in the pyrometamorphic phosphide assemblages of the Hatrurim Formation (the Dead Sea area, Southern Levant) and was named for the occurrence on the Transjordan Plateau, West Jordan. Later on, the mineral was confirmed in the Cambria meteorite (iron ungrouped, fine octahedrite), and it likely occurs in CM2 carbonaceous chondrites (Mighei group). Under reflected light, transjordanite is white with a beige tint. It is non-pleochroic and weakly anisotropic. Reflectance values for four COM recommended wavelengths are [Rmax/Rmin, % (λ, nm)]: 45.1/44.2 (470), 49.9/48.5 (546), 52.1/50.3 (589), 54.3/52.1 (650). Transjordanite is hexagonal, space group P62m; unit-cell parameters for the holotype specimen, (Ni1.72Fe0.27)1.99P1.02, are: a = 5.8897(3), c = 3.3547(2) Å, V = 100.78(1) Å3, Z = 3. Dcalc = 7.30 g/cm3. The crystal structure of holotype transjordanite was solved and refined to R1 = 0.013 based on 190 independent observed [I > 2σ(I)] reflections. The crystal structure represents a framework composed of two types of infinite rods propagated along the c-axis: (1) edge-sharing tetrahedra [M(1)P4] and (2) edge-sharing [M(2)P5] square pyramids. Determination of unit-cell parameters for 12 members of the Fe2P–Ni2P solid-solution series demonstrates that substitution of Ni for Fe in transjordanite and vice versa in barringerite does not obey Vegard’s law, indicative of preferential incorporation of minor substituent into M(1) position. Terrestrial transjordanite may contain up to 3 wt% Mo, whereas meteoritic mineral bears up to 0.2 wt% S.

Mineralogical, Geochemical, and Rock Mechanic Characteristics of Zeolite-Bearing Rocks of the Hatrurim Basin, Israel

“…Fascinating mineralogical assemblages in rocks and their weathering products account for more than 240 mineral species. Most of them are rare or extremely rare, the Hatrurim Basin being the type locality for more than 20% of them (e.g., [14][15][16]).…”

Ultrahigh-Temperature Sphalerite from Zn-Cd-Se-Rich Combustion Metamorphic Marbles, Daba Complex, Central Jordan: Paragenesis, Chemistry, and Structure

“…S-rich organic matter is an important carrier of Ni, V, and sometimes Cu [14]. These very rocks are the sedimentary protoliths of CM marbles with unique accessory U, Cd, Zn, and Ni mineralogy [4,7,9,10,14,[18][19][20]22,23].…”

“…CM alteration of the sedimentary rocks rarely occurs in reduced conditions, at an excess of fuel over oxidant. Nevertheless, diverse sulfides [4,16,19,20], such as zoharite ((Ba,K) 6 (Fe,Cu,Ni) 25 S 27 ) [12], K-Fe-Cu-Ni sulfide [5], ZnS, and Ag-S compounds [19,20]; native elements [6]; and phosphides, including halamishite (Ni 5 P 4 ), negevite (NiP 2 ), transjordanite (Ni 2 P), and polekhovskyite (MoNiP 2 ), have been progressively more often found in CM rocks of the Mottled Zone [6][7][8][9][10][11].…”

“…Other oxide accessories with essential Ni contents are spinel-group minerals, periclase, Ca ferrites, and silicoferrites [15,93,114]. On the other hand, more than 10 oxygen-free Ni minerals were found in reducing assemblages from the MZ complexes: kamacite (Fe,Ni) [6]; numerous Ni-and Fe-Ni-phosphides (schreibersite ((Fe,Ni) 3 P), baringerite ((Fe,Ni) 2 P hex ), murashkoite ((Fe,Ni)P), allabogdanite ((Fe,Ni) 2 P rhomb ), zuktamrurite ((Fe,Ni)P 2 ), halamishite (Ni 5 P 4 ), negevite (NiP 2 ), transjordanite (Ni 2 P), polekhovskyite (MoNiP 2 ), nazarovite Ni 12 P 5 [6,7,[9][10][11][115][116][117][118], millerite and/or mäkinenite (Ni(S,Se)) [4,16], zoharite [12], and pentlandite; as well as a number of unidentified Ni phases, including Ni 2 As and K-Fe-Cu-Ni sulfide [5,6,93]. This long list has been extended with Ni oxychalcogenides revealed in the Jordanian CM marbles.…”

Discovery of terrestrial andreyivanovite, FeCrP, and the effect of Cr and V substitution on the low-pressure barringerite-allabogdanite transition

“…The Hatrurim Complex has recently become known as a source of terrestrial phosphides (Britvin et al 2015). Here, besides the phosphides typical of meteorites: schreibersite, Fe 3 P (Britvin et al 2021a), barringerite, Fe 2 P (Britvin et al 2017) and its high-pressure analogallobogdanite (Britvin et al 2021b), nine new phosphides: halamishite, Ni 5 P 4 (Britvin et al 2020a); negevite, NiP 2 (Britvin et al 2020b); nazarovite, Ni 12 P 5 (Britvin et al 2022a); zuktamrurite, FeP 2 (Britvin et al 2019a); transjoardanite, Ni 2 P (Britvin et al 2020c); polekhovskyite, MoNiP 2 (Britvin et al 2022b); murashkoite, FeP (Britvin et al 2019b); nickolayite, FeMoP (Murashko et al 2019); orishchinite, Ni 2 P (Britvin et al 2019c) were discovered. This detection of phosphides in the rocks of the Hatrurim Complex is unexpected.…”