Motivated by previous largely absent high-quality soil chemical data, the samples were taken in parallel to repetitive soil respiration determinations at the same locations and sites (not part of this data set). Quality-controlled (GEMAS protocol) soil chemical data are presented (64 elements with all major and minor plus most trace elements) from two mineral soil layers (TOP = 0–20 cm; BOT = 30–50 cm). Material was taken repetitively in both dry and rainy season at the same 13 locations across the state of Amazonas, Brazil, from Feb/Mar 2016 to Feb/Mar 2017. The material roughly represents an area of 740,000 sqkm. All samples are from ferralsols/oxisols. Each location is divided into a forest site and a deforested (post-forest) site with different land use (pasture, plantation, agroforest). All work was part of the NOPA project EcoRespira-Amazon. Samples were taken with a manual auger using discardable glove-protected hands for handling. The fresh bulk samples were double-bagged in the field in Rilsan bags (water and gas tight) and transported to our labs at TU Bergakademie Freiberg. All materials were oven-dried at room temperature (25°C), crushed and aliquoted for the various chemical digestions, and the archive. Aliquots were analyzed after making pressed-powder pellets and glass-fusion discs by WD-XRF (major and minor elements, a few trace elements), after full multi-acid digestion by ICP-OES and ICP-QMS (some major and minor elements, all trace elements), and by elemental analysis after direct inweight for total and organic carbon, for nitrogen and sulfur.