The HED meteorites are a grouping of achondrite meteorite types, the:
- Olivine Diogenites
These are all thought to have originated from the crust of the asteroid 4 Vesta, their differences being due to different geologic histories of the parent rock. Their crystallization ages have been determined to be between 4.43 and 4.55 billion years from radioisotope ratios.
- http://www.lpi.usra.edu/meetings/lpsc2003/pdf/1502.pdf OLIVINE DIOGENITE NWA 1459: PLUMBING THE DEPTHS OF 4 VESTA, A. J. Irving, et al., Lunar and Planetary Science XXXIV (2003)