Micrometeorite NMM 834 is the type specimen of radial crystallisation in porphyritic olivine (PO) MMs, known from one full page (159) in the Atlas of Micrometeorites.
NMM 834 - Forskerfabrikken
This is a “giant” micrometeorite, ~0.5 mm, jet black, and with a beautiful golden nickel-iron metal bead in the front, the apex of the crystallisation. Radial olivine is otherwise known from meteoritic chondrules, but here is a rare example in a micrometeorite.
The image from the electron microscope (SEM) reveals another surprise: a ~30µm chromite crystal, plus small magnetite crystals in the crevices between the large olivine (forsterite) crystals. This little Space rock has it all! A museum-quality micrometeorite.
PROVENANCE: The catalogue number refers to the NMM archive, the index of Jon Larsen’s Project Stardust collection, which is the reference collection for urban micrometeorites. The stone was found, curated, and selected by Larsen. It is in pristine condition, fresh from Space. Follow Jon Larsen’s Project Stardust and get exclusive micrometeorite content: https://www.patreon.com/c/ProjectStardust826
VERIFICATION: The MM has been confirmed extraterrestrial by visual identification and/or SEM/EDS analysis by Jon Larsen. The stone is mounted on a durable aluminium/glass/cardboard microslide and is delivered together with a signed Certificate of Authenticity and four photo files. This micrometeorite is a unique museum-quality specimen and a jewel in any collection.