The ternary diagram TiO 2 -FeO*-MgO (FeO* = FeO + MnO) is proposed as a quantitative objective tool for distinguishing between primary magmatic biotites and those that are more or less reequilibrated, or possibly neoformed, by or within a hydrothermal fluid. The limit of the domains of the primary magmatic biotites, the reequilibrated biotites and the neoformed biotites were determined on the basis of optical, paragenetic and chemical criteria.

Isli and Tislit, the Moroccan "Romeo and Juliette" according to a popular legend gave their name to a twin lakes in Imilchil. There we show evidences that these two lakes are impact craters. The proof as follow: 1) the fragments of iron meteorites found on both sides of Isli and Tislit lakes belong to the same parent meteorite and siderite type; 2) the sedimentary formations which are almost tabular in the area of the lakes become tilted with a centripetal sloping all around and towards Isli lake; 3) the circular shape of the Tislit lake is similar to that of the Isli lake; 4) the impact breccias found on the south of the Isli lake contain shocked quartz crystals; 5) the radial fractures of high pressure affect some sedimentary beds. All these observations give evidence of the presence of an impact crater due to the fall of meteorites.

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Meteorites are rocks that once were part of planets or large asteroids, and usually contain a great amount of extra‐terrestrial iron. Nowadays, the meteorite business is booming and the demand is increasing all over the world, whereas supply (originating especially from Morocco and Algeria) is limited. Thus, specimens presented as meteorites often turn out to be common Earth rocks or old smelter and castoff iron dubbed as a ‘meteor‐wrong’. In the present study, a compact handheld instrument based on fast‐response multi‐elemental analysis technique, i.e., laser induced breakdown spectroscopy (LIBS), has been used to identify specific major elements (Ni and Co) and trace elements (Ga and Ir), in order to discriminate a certified iron meteorite with respect to a suspected meteorite fragment and a pig iron product. Furthermore, a calibration freeLIBS method has been used to quantify the main elements Fe, Ni and Co in the iron meteorite and Fe, Mn, Si and Ti in the other two fragments.

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