Great challenges are often faced in recovering intact samples from tailings with sandier matrices for carrying out laboratory tests. These difficulties often limit the characterization of these materials to the use of reconstituted samples, whose ability to reproduce the in-situ behavior of the tailings is inherently linked to the ability of the sample preparation method to reproduce the material matrix. Several studies have demonstrated that the behavior of sandy tailings under lows and highs deformations are affected by the methods used to prepare the samples and the present study seeks to understand how the microstructure can interfere with such variations. Seeking to delve deeper into this topic, the research aimed to carry out physical, chemical, mineralogical and microstructural characterization tests of a sample of filtered iron ore waste, predominantly sandy, testing three sample reconstitution techniques: Moist tamping (MT), Water pluviation (WP) and Slurry deposition (SD), evaluating the change in the response of the material s microstructure to different molding techniques. X-ray computed microtomography analysis tests were carried out on the prepared material with different void indices, being: 0.70, 0.75 and 0.80. At the end of each preparation, the samples were subjected to instant freezing using liquid nitrogen. With the results in hand, significant variations were observed between the study sample preparation methods, regarding the arrangement of particles in the medium, empty spaces (porosity) and the influence of the saturation of the specimen. The results obtained from microcomputed tomography tests indicated a disoriented and macroporous arrangement between the sample reconstitution techniques, observing microstructural similarity between the MT and WP techniques, both by visual observation and by evaluation of microstructural attributes. The MT technique tends to form lumps during the socket compaction process, forming a structure known as a honeycomb, which can well simulate the stacking of compacted waste. The WP technique, due to its natural sedimentation process, also tends to form voids due to the arrangement of the particles, being more susceptible to segregation. Despite this, the WP technique can also be applicable for hydraulic deposits due to the natural sedimentation process without compaction effort. The SD technique produces a specific waste matrix, influenced by the homogenization process. This uniformity of the samples observed in the SD technique may well represent hydraulic deposits, depending on the waste disposal conditions. Finally, the research sought to evaluate the microstructure of an iron ore tailings through the matrix generated by each sample reconstitution technique, identifying aspects that can influence the arrangement and distribution of grains in the environment and macroporosity. Instant freezing can preserve the characteristics of the samples; however each technique has its limitations and individualities, which were addressed in this work, and must be used with caution to define the technique to be adopted depending on the condition of the in-situ waste for the purpose of comparison.