Famenin        35°7.12’N, 48°58.50’E

Hamadan, Iran

Confirmed fall: 2015 June 27

Classification: Ordinary chondrite (H/L3)

History: Around 08:30 am local time (GMT+3.5) on 27 June 2015, Reza Salimi, living in Famenin town of Hamedan Province, Iran, heard the sound of an impacting object onto the roof of his house. He discovered that part of the roof was damaged and fragments of a stone were spread on the roof. He found some other fragments in his yard. News of the meteorite fall propagated quickly via the local media. With the help of a local journalist, Hamed Pourkhorsandi (CEREGE) received a total of 25 g of fragments two weeks after the fall. Gamma spectroscopy of the two larger fragments were carried out from 16 to 24 July 2015 in LSCE, France. The data show the presence of ⁷Be, ⁵⁴Mn, ²²Na and ²⁶Al. The presence of these short-lived nuclides, and the detailed reports in the media support with a recent fall event.

Physical characteristics: Upon its impact to the roof, the meteorite broke into two large and eight smaller fragments. The meteorite is covered by fusion crust. The interior is light gray and chondrules are visible with the naked eye.

Petrography: Petrographic observations, performed by optical microscopy and SEM, show different types of chondrules set in a clastic matrix. Chondrule average apparent diameter is 615±380 μm (N=32). Some chondrules exhibit well-preserved troilite rims. Olivine and low-Ca orthopyroxene are not completely equilibrated. Type I chondrules containing metal grains are present. Sub-spherical Fe-Ni metal grains are present in the matrix and show intergrowths with troilite. Troilite is finely polycrystalline with domains of about 10 μm. No melt veins nor shock darkening are visible.

Geochemistry: Olivine Fa_17.4±3.7 (Fa_6.4-24.9, PMD 14%, N=23), low-Ca pyroxene Fs_17.1±9.0Wo_1.8±1.5 (Fs_5.4-31.0, PMD 41%, N=7) . Cr₂O₃ content of olivine is 0.12±0.16 wt%. Magnetic susceptibility (measured on 25 g) log χ (× 10^-9 m³/kg) = 5.08. Saturation magnetization is 26.0 Am²/kg, indicating a bulk metal content similar to L chondrites (see Gattacceca et al. 2014).

Classification: H/L3. Olivine composition is in the range of H chondrites. However magnetic susceptibily is intermediate between H (log χ (× 10^-9 m³/kg) = 5.32±0.10, N=145 falls) and L chondrites (log χ (× 10^-9 m³/kg) = 4.87±0.10, N=144 falls in Rochette et al. 2003). The bulk metal content determined by hysteresis measurements is in the L range. Chondrule size is closer to the range for L chondrites than for H chondrites. Based on this, Famenin is classified in the intermediate category H/L (as defined in Kallemeyn et al. 1989). The petrographic subtype (3.8/3.9) is based on petrographic observations and the scatter of olivine composition.

Specimens: 24 g and a polished section at CEREGE.