Sandstone nodules.( concretions ).
Fossiliferous nodules from Steinhardt Quarry. (A) Sandstone concretions... | Download Scientific Diagram
Beach Stones with Iron at Rhossili – Jessica's Nature Blog
Navajo Ss concretion, 3D view
Models of iron oxide concretion formation: field, numerical, and laboratory comparisons - CHAN - 2007 - Geofluids - Wiley Online Library
Pondering puzzling patterns in sandstone | Colorado Arts & Sciences Magazine Archive | University of Colorado Boulder
Composition, nucleation, and growth of iron oxide concretions - ScienceDirect
Glad You Asked: What are Moqui marbles? - Utah Geological Survey
Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars | Science Advances
Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars | Science Advances
Iron-oxide concretions and nodules | Some Meteorite Information | Washington University in St. Louis
Glad You Asked: What are Moqui marbles? - Utah Geological Survey
Spheroidal concretions with iron-oxide rinds (site RG, Fig. 1). (A)... | Download Scientific Diagram
Fe-oxide concretions formed by interacting carbonate and acidic waters on Earth and Mars | Science Advances
Biologic Origin of Iron Nodules in a Marine Terrace Chronosequence, Santa Cruz, California - Schulz - 2010 - Soil Science Society of America Journal - Wiley Online Library
Identity Help : Identified! Oklahoma Reduction Spheroids
Self-organized iron-oxide cementation geometry as an indicator of paleo-flows | Scientific Reports
Ironstone - Wikipedia
Minerals | Free Full-Text | Genesis of Pyrite Concretions: Constraints from Mineral and Geochemical Features of Longtan Formation in Anhui Province, Eastern China
Iron-oxide concretions and nodules | Some Meteorite Information | Washington University in St. Louis
Understanding genesis of iron oxide concretions present in Dhandraul (Vindhyan) Sandstone: Implications in formation of Martian hematite spherules | SpringerLink
Iron-oxide concretions and nodules | Some Meteorite Information | Washington University in St. Louis
Chert nodule – Geology is the Way
Iron-oxide concretions and nodules | Some Meteorite Information | Washington University in St. Louis
Iron-oxide concretions and nodules | Some Meteorite Information | Washington University in St. Louis
31 Moki Marbles Images, Stock Photos & Vectors | Shutterstock
![PDF] Characterization of Navajo Sandstone concretions: Mars comparison and criteria for distinguishing diagenetic origins | Semantic Scholar](https://ai2-s2-public.s3.amazonaws.com/figures/2017-08-08/40810d156b2d5570aa62caf0dc026f72ae2c61fd/4-Figure1-1.png "PDF] Characterization of Navajo Sandstone concretions: Mars comparison and criteria for distinguishing diagenetic origins | Semantic Scholar")