Table 3.
Cr isotope results for analyzed olivine (Ol) and chromite (Chr).
| Meteorite | Phase | Fe/Cr | Mn (ppm) | Cr (ppm) | 55Mn/ 52Cr | ± (10%) | ε53Cr | ± | ε54Cr | ± | ε53Cr CORR | ± | 53/52Cr (±) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Seymchan | Ol | 695.8 | 2,641 | 197 | 15.14 | 1.51 | 1.69 | 0.36 | 0.14 | 0.50 | 1.55 | 0.38 | 0.1134775 (0.0000043) |
| Sericho | Ol | 270.9 | 1,259 | 353 | 4.07 | 0.41 | 0.54 | 0.14 | 0.04 | 0.08 | 0.42 | 0.18 | 0.1134648 (0.0000020) |
| Fukang | Ol | 349.1 | 2,949 | 353 | 9.49 | 0.95 | 1.07 | 0.10 | −0.16 | 0.19 | 1.00 | 0.15 | 0.1134714 (0.0000017) |
| Brenham | Ol | 7.46 | 0.75 | 0.86 | 0.04 | −0.06 | 0.11 | 0.77 | 0.11 | 0.1134687 (0.0000013) | |||
| Average | Ol | 1.04 | 0.97 | −0.01 | 0.26 | ||||||||
| Hambleton | Chr | −0.15 | 0.07 | −0.8 | 0.10 | ||||||||
| Seymchan | Chr | 0.31 | 4,800 | 484,500 | 0.011 | 0.001 | −0.09 | 0.07 | −0.53 | 0.13 | 0.1134590 (0.0000008) | ||
| Sericho | Chr | 0.33 | 3,900 | 489,800 | 0.009 | 0.001 | 0.03 | 0.07 | −0.40 | 0.13 | 0.1134603 (0.0000008) | ||
| Fukang | Chr | 0.45 | 3,900 | 339,700 | 0.013 | 0.001 | 0.04 | 0.10 | −0.57 | 0.20 | 0.1134605 (0.0000011) | ||
| Brenham | Chr | 0.30 | 3,400 | 492,400 | 0.008 | 0.001 | −0.04 | 0.07 | −0.44 | 0.13 | 0.1134595 (0.0000008) | ||
| Average | Chr | −0.04 | 0.16 | −0.49 | 0.31 |
The spallation corrected ε53Cr values are the mean of the corrected values calculated using the ureilites and enstatite chondrites as initial ε54Cr compositions for olivines. For the chromites, the spallation correction was not required due to the very low target nucleus/Cr ratio. Brenham olivine values are taken from (42). The errors on the average values (underlined) are 2 SD, errors on samples are 2 SE.