Pyrophyllite and talc are both tetrahedra–octahedra–tetrahedra (TOT)-type phyllosilicates, but differences can be found in the stacking mode of the layers and the ion occupation. Fourier transform infrared spectroscopy was used to differentiate between pyrophyllite and talc. In the 400–600 cm⁻¹ region, pyrophyllite exhibits six peaks, while talc only exhibits five peaks. In the 1000–1200 cm⁻¹ region, pyrophyllite exhibits three clear peaks at approximately 1051, 1070, and 1121 cm⁻¹; while talc only exhibits one strong peak near 1020 cm⁻¹. The differences between pyrophyllite and talc in the near–infrared (NIR) region are clear in the 4000–4700 cm⁻¹ region, and pyrophyllite exhibits an intense peak around 4615 cm⁻¹, which is attributed to the combination of the OH and Si-O-Si stretching bands. Talc has a maximum peak located near 4324 cm⁻¹, which is attributed to the OH stretching vibration. In addition, talc has a secondary peak near 4366 cm⁻¹. Talc has two other weaker peaks around 4054 and 4180 cm⁻¹. The 7000–7250 cm⁻¹ region exhibits the first fundamental overtone of the OH group stretching vibrations. The common characteristic band of these two minerals is 7175–7183 cm⁻¹. The first overtone of OH stretching vibrations can also be generated by adjacent peaks in the fundamental overtones. The peaks of these two minerals around 7094 cm⁻¹ appear to be a combination of 3630 (±5) cm⁻¹ and 3642 (±3) cm⁻¹.The factor of the first fundamental overtone of the OH group stretching vibration is 1.95 (±0.003). Therefore, the characteristic peaks in the mid-infrared (MIR) and NIR regions can be used to distinguish between pyrophyllite and talc, providing a research basis for further exploration in related geological areas.

Two bacterial strains, designated LXY-1^T and LXY-4^T, were isolated from soil samples collected at a heavy metal smelting plant located in Guangxi, China. Phylogenetic analysis indicated that these strains formed two distinct lineages within the genus Neobacillus. Both strains were characterized as facultative anaerobic, Gram-positive staining, endospore-forming, non-motile, short-rod bacteria. The major cellular fatty acids identified in these strains included C_16:0, iso-C_15:0, antéiso-C_15:0, and antéiso-C_17:0. The predominant polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), and phosphatidylglycerol (PG). The average nucleotide identity (ANI) values between the newly isolated strains and their closest phylogenetic relatives, the type strains of the genus Neobacillus, were found to be below 95%, with corresponding digital DNA–DNA hybridization (dDDH) values remaining below 70%. Based on a comprehensive polyphasic taxonomic analysis incorporating chemotaxonomic, phenotypic, phylogenetic, and genomic data, we proposed that strains LXY-1^T and LXY-4^T represent two novel species of the genus Neobacillus, for which the names Neobacillus terrisolis sp. nov. and Neobacillus solisequens sp. nov. are designated. The type strains are LXY-1^T (= CGMCC 30313^T = JCM 37671^T) and LXY-4^T (= CGMCC 1.62901^T = JCM 37672^T), respectively.

A newly discovered facultative anaerobic strain, designated as LXY-3^T, was obtained from a soil sample collected at an industrial site in Guangxi, China, known for heavy metal processing. An investigation including phenotypic, chemotaxonomic, and genomic traits was conducted. Phylogenetic analysis based on 16S rRNA showed that LXY-3^T belonged to the genus Paenibacillus. The closest phylogenetic relative of this strain was Paenibacillus anaericanus MH21^T with the similarity of 97.03%. Iso-C_15:0, antéiso-C_15:0, and C_16:1 ω7c alcohol were the major cellular fatty acids. The predominant polar lipids comprised diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), phosphatidylglycerol (PG), unidentified phospholipids (PL1-PL8), unidentified resistant material (RM1–RM4), and lipids (L1–L3). For genome sequencing, the genomic DNA G+C content of the strain is 51.2 mol%. Comparative genomic analysis revealed that the average nucleotide identity (ANI) values between strain LXY-3^T and its closest phylogenetic relatives within the genus Paenibacillus (represented by type strains) were consistently below the 95% species demarcation threshold. Nitrogen fixation gene cluster (nifB, nifE, nifK, nifN, nifV, nifX, nifD, and nifH) was conserved in the strain. Correspondingly, digital DNA–DNA hybridization (dDDH) values remained below the 70% cutoff for species delineation. These genomic metrics provide compelling evidence that strain LXY-3^T represents a novel species within the genus Paenibacillus. The type strain LXY-3^T (=CGMCC 1.64949^T = JCM 37600^T) is proposed.