The meteorite exhibits a beautiful and well-formed Widmanstätten pattern, with kamacite lamellae (L/W ~ 25 and width 1.1 + 0.1 mm), with variation in brightness between the lamellaes. Due to the structure presented, Nova Petrópolis belongs to the structural group of medium octahedrites. Neumann lines cross the entire meteorite, in different directions, from the edges to the inclusions, generally crossing several kamacite granules, which are sometimes reflected in the passage of these granules. The plessite and taenite fields occupy about 20-30% of the examined surface, being varied in shape and structure. The sulphide grains are not only very bulky but also very small. Under the microscope, Nova Petrópolis shows that it consists essentially of kamacite, plessite, and taenite, with smaller amounts of troilite, daubréelite, chromite and schreibersite and accessory amounts of carlsbergite. Description obtained in the documents of Nacional Museum.
7.8% Ni, 19.9 ppm Ga, 36.5 ppm Ge and 9.4 ppm Ir
Iron Meteorite - Medium Octahedrite IIIAB.
H. GrunewaldtJ and J. T. Wasson
At the end of the 70s, a road was being opened in the Nova Petrópolis city through a backhoe, when they found a very heavy block looking like iron. This block was kept in a garage and became known as "cry" - in fact condensation water during sudden changes in temperature. In 1982 the doctor Hardy Grunewaldt learned about the block and, recognizing it as a meteorite, acquired it. Half of the block went to the National Museum and the other half stayed with Dr. Hardy. The Museum had contact with the meteorite and offered to treat it and saw off a piece to obtain fragments of 100 to 200 grams. This was done through a slow and painful learning process, with the collaboration of several laboratories from the UFRGS School of Engineering. Once the process was completed, a fragment worth more than 1500 reais was incorporated into the Museum's collection, beem a iron meteorite with spectacular structures from Widmanstätten, waterproofed with 3 coats of acrylic resin. It is one of the 4 meteorites known from Rio Grande do Sul State and, besides the owner, only the Museum has a fragment. Source: