Portales Valley, 1998 New Mexico Hammer Fall, Micromount

$5.00

On June 13th, 1998, a spectacular fireball lit up the morning sky over rural Roosevelt County New Mexico. A shower of meteorites fell over a wide area and one of them penetrated the roof of a barn and embedded itself in the wall. Later analysis revealed that the stones had brilliant melt veils of metals that criss-crossed the stony matrix. It is officially classified as an H6 chondrite.

Refer to the photo. The black centimeter cube is shown for scale and is not included. You are purchasing a single small fragment like the one shown. Your purchase will include a labeled gemjar for safe storage.

From the Meteoritical Bulletin entry on Portales Valley :

Portales Valley

Roosevelt County, New Mexico, USA

Fell 1998 June 13, ~07:30 MDT (~13:30 UT)

Ordinary chondrite (H6)

After detonations were heard and smoky trails seen in the sky, a shower of meteorites landed near Portales, New Mexico. 53 objects have been recovered, with a total mass of 71.4 kg. The largest pieces weighed 16.5 kg (witnessed to fall by Nelda Wallace and Fred Stafford), 17.0 kg (found by Elton Brown), and at least nine others over 1 kg. A 530 g fragment went through the roof of Gayle Newberry's barn and embedded itself in a wall, indicating a trajectory west to east. The elliptical strewn field is approximately 7.7 ´ 2 km, trending N60–65ºE, although recent reports may extend this somewhat.

 ...olivine indicates shock stage S1, plagioclase indicates S2–S3, and abundant opaque shock veins suggest S3 or higher (discrepancies may be due to annealing).  Macroscopic description (D. A. Kring, UAz ): Some individuals are crosscut by an unusually high number of metal-rich shock veins, and some specimens are composed dominantly of metal. These metal-rich samples appear to be large single veins, or pockets of metal produced by intersecting veins. Angular chondritic clasts may have moved a few millimeters along metal-rich veins.  Etching of centimeter-sized metal areas reveals a fine Widmanstätten pattern, bandwidth = 0.02 to 0.81 mm (average 0.32 mm). The composition of kamacite in metal-rich regions is the same as metal in chondritic areas (0.56 ± 0.05 wt% Co). The source of the metal in the shock veins appears to be the H-chondrite host, which is depleted in its normal complement of metal (4.4% rather than 15–19%).