Calama 082        22°8.50’S, 68°37.37’W

Antofagasta, Chile

Find: 19 Oct 2019

Classification: HED achondrite (Diogenite, polymict)

History: The numerous fragments of meteorite were collected over 50 m² by Mr. Ilya Chaplygin, who was searching for meteorites in the Atacama Desert.

Physical characteristics: Physical properties: The meteorite has more than 100 fragments. The largest pieces are 843, 476 and 350 g. The stone of 843 g of mass has isometric shape; half of the stone surface is covered with dark-gray fusion crust. Smaller fragments have not fusion crust and are dark gray in color. The brecciated texture is visible. Total mass of collected fragments is 2850 g.

Petrography: (Lorenz C. A., Vernad) the meteorite has brecciated texture. The poorly sorted breccia comprises of fragments of pyroxenites, melt matrix breccias, minor fragments of pyroxene-feldspar rocks, recrystallized breccias and sulfide-silicate breccias settled in the fine-grained clastic matrix. Main phase is pyroxene; feldspar is minor, olivine, chromite, silica, troilite and metal are rare. The melt matrix breccia fragments are up to 2 cm of size. The rock is crossed by rare shock melt veins.

Geochemistry: Mineral compositions and geochemistry: (N. N. Kononkova, EMPA, Vernad; T. Kryachko, SEM, Technograd, Moscow): Low-Ca pyroxene is En63.5-En₇₉Wo_1.4-4.5 (Fe/Mn=21.5-35.3); Olivine Fo_62.3-66.3; Pyroxene in eucritic fragments En_37-62Wo_2.4-4.4 with lamellae of En_41.5-50.5Wo_41.5-44.6. Feldspar An_87.4Ab_11.6-An_91.9Ab_8.1

Classification: polymict diogenite

Specimens: The type specimen of 564.3 g and four thin sections are on deposit at Vernad. Mr. Chaplygin holds the main mass.