Ablaketka        49°51.27’N, 82°48.89’E

East Kazakhstan, Kazakhstan

Fall: 16 Feb 2018

Classification: Ordinary chondrite (H5)

History: The fall occurred on the 16 Feb 2018 at 14:43:37 UTS. Residents of Ablaketka, a suburb of Ust-Kamenogorsk, Kazakhstan, watched a bright bolide moving approximately north and accompanied by an explosion. The bolide was recorded by video camera mounted on a locomotive moving NE from Charsk. The first sample was discovered by Mr. Alexander Baranov on February 18, near the Irtysh river, on a field covered by snow ~10-20 cm deep. The fall left two scratchy traces: the first was ~0.5 m in length, excavating snow and some soil; the second scratch, 8 m away, was terminated by a channel in the snow where the stone was found. On Feb. 22, two other pieces were recovered by anonymous finders. Later, about 10 pieces were collected by anonymous persons from Feb to Apr 2018, in a strewn field of 1 × 5 km, on an azimuth of 20°, with central coordinates of 49°51.27’N, 82°48.89’E.

Physical characteristics: The stone discovered first is 763 g and covered by black fusion crust, with only a few small broken parts, displaying light-gray interior. Two smaller individuals are 63.5 and 266.6 g. Later, several individual samples with dark-grey- to black interior were recovered. The masses of individuals are in a range 0.1-1.2 kg. A total collected mass of the meteorite shower is approximately 5.5 kg.

Petrography: The meteorite has brecciated, chondritic texture. Macroscopically, a light-gray chondritic host contains cm-sized clasts of dark-gray chondritic lithology (~20 vol%). The clasts have sharp contacts with the host. The host is composed of chondrules and chondrule fragments, mineral clasts and fine-grained, recrystallized, silicate matrix. The main phases are olivine, pyroxene, FeNi metal; minor phases are devitrified glass, feldspar, troilite; spinel is accessory. Olivine has weak undulatory extinction and planar fractures. Impact melt veinlets and melt pockets are present in the host chondite. The dark lithology has the same texture and composition of the silicates, but is intensive darkened. It has high abundance of tiny inclusions and narrow veinlets of troilite, occurring in the fractures and along the grain boundaries. Several objects in the dark lithology are fine-grained, silicate breccias with troilite matrix. The olivine demonstrates strong undulatory extinction and planar fractures decorated by opaque inclusions.

Geochemistry: Mineral compositions and geochemistry: (N. N. Kononkova, EMP, Vernad): Olivine Fa_{19.1± 0.4} (N=24), Pyroxene Fs_17.1±0.6Wo_1.4±0.2 (N=23).

Classification: (C. A. Lorenz, Vernad) ordinary chondrite (H5, monomict breccia) Shock stage is S3; weathering grade is W0.

Specimens: Two thin sections and two samples of 108.7 and 57.2 g are on deposit in Vernad; anonymous collectors hold the main mass.