See Contributor's comments below. H6
TKW 367 grams (from the MetBul Database. Does not reflect additional finds). Observed fall 17 November 1981, Loei, Thailand (note that the MetBul Database provides coordinates that are in Laos).
   
Jnmczurich writes:
A small group of four Chiang Khan individuals totalling 67.9g (45.5g, 12.2g, 7.3g, 2.9g). The largest individual is fully crusted, distinct oriented with bubble crust and roll-over lip at the edges. It appears that all the individuals have a very thick crust of about 1 mm thickness. Obtained from two different but trustworthy private collector sources (1989, 1992 and 1995).
An image of the largest Chiang Khan individual known (682 g) can be found in "Field Guide and Catalogue of Meteorites" (different issues 1989-1997) by R. Haag.
Place of fall: Chiang Khan, Loei, Thailand, very close to the Mekong river on the Thailand-Laos border.
The MetBul gives coordinates of approximately 17°54' N., 101°38' E, which is a few meters into Laos. The stones also fell in Thailand and into the Mekong river.
Classification: H6 chondrite. Olivine Fa 18 mol%, Fe total 26.98%. First classification was H5 chondrite, Fa 19.8 mol%.
From MetBase 7.2 (2005):
After a bright fireball and detonations, 31 pieces, totalling 367g, the largest 51.3g, were recovered from the town of Chiang Khan, on the Thailand-Laos border, Met. Bull. 60, Meteoritics, 1982, 17, p.94. Circumstances of fall, R.Bhavli, Meteoritics, 1983, 18, p.266 (abs.). Description, fall date given as November 18, classification as H5, petrology, olivine Fa19.8, K.Yagi et al., Mineral. Petrol., 1989, 40, p.173. Bulk chemical analysis, 26.98% total Fe, E.Jarosewich, Meteoritics, 1990, 25, p.323. Description of two fragments, V.K.Nayak, Papers 15th Symp. Ant. Met., NIPR Tokyo, 1990, p.204 (abs.). A large number of specimens have been subsequently recovered from the Laos site of the border, R.Haag, priv. comm., 1991. Noble gas concentrations, regolith breccia, T.Loeken et al., Meteoritics, 1992, 27, p.251 (abs.); see also, Chem. Erde, 1992, 52, p.249. Noble gas isotopic abundances, cosmic-ray exposure age, 2.7±0.4 Ma, O.Eugster et al., GCA, 1993, 57, p.1115; see also, LPSC, 1990, 21, p.339 (abs.). Comparison of pyroxene and plagioclase geothermometry, J.A.Chamot and H.Y.McSween,Jr., LPSC, 2000, 31, abs. #1426. Magnetic susceptibility, P.Rochette et al., MAPS, 2003, 38, p.251.
Repository information according MetBase 7.2 (2005) listed a total of 1491.9g, distributed to 28 different collections (12 private collections, 16 university or similar collections).
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