Fig. 2

Concretions collected from the Red Breaks site, Utah. (A) RB01, diameter 9.5 mm, weight 1.2262 g, showing a rough, reddish-brown surface. (B) RB05, diameter ~ 50 mm, weight ~ 17 g; top image shows the concretion in situ, demonstrating its geological context, bottom image after extraction for laboratory analysis. Red arrows indicate orientation lines. (C–J) RB10, diameter 36 mm, weight 45.5 g, displaying various views and cut sections. (C) Top view where red arrow highlights visible layering, (D) bottom view, (E) edge view, (F–J) cut sections revealing internal structure, including the contrast between the outer rind and inner core (visible in G, I, J). Note the color variations from reddish-brown (RB01, RB05) to greenish grey (RB10), reflecting differences in mineralogy or weathering. Observe the textural differences between the rough surface of RB01 and the smoother surfaces of RB05 and RB10. Scale bars = 1 cm for A, 2 cm for B-J. The visible layering, color variations, and internal structures provide crucial information about the formation processes and potential for preserving magnetic signatures over time. These concretions demonstrate the range of sizes and internal structures found at the study site, offering insights into formation processes and potential magnetic recording capabilities.