Mineral: Topaz
Locality: Katlang, Mardan District, Khyber Pakhtunkhwa, Pakistan
Dimensions: 12 x 7.5 x 13 cm / main crystal: 5.4 cm.

Description: Mass: 1050 g MIM number: 2217 The likely geological history of the formation of this superb sample can be easily read by inspection: A large crystal of red topaz measuring at least 13 cm formed first, then got cleaved into 4 pieces by the tectonic deformations of the medium in which it was found (hence the nickname "the rocket" as they look similar to the stages of a spatial step rocket). These were subsequently displaced from their initial position by the natural movements of the medium and then “frozen” in calcite (more precisely in a light-colored tectonic breccia, which formed above a grey carbonatite). The 4 pieces do not show the same width: the section of a topaz crystal being rectangular, these pieces probably rotated before getting frozen. Part of the breccia was removed to expose the pieces of topaz that show a superb red color that is very rare for this mineral (coloration due to chromium which also imparts a strong UV fluorescence, and to the absence of natural radioactivity which would have transformed it into a sherry color as is the case for the Brazilian imperial topazes). Photographer: AINU / Augustin de Valence; Publication: "Rocks & Minerals: Vol. 98, No.6 Nov/Dec 2023"

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