Elemental and stable isotope data measured in Eocene foraminiferal calcite from Ocean Drilling Program Site 865 and Tanzanian Drilling Project Site 18 published in Edgar et al. (2015) "Assessing the impact of diagenesis on δ11B, δ13C, δ18O, Sr/Ca and B/Ca values in fossil planktic foraminiferal calcite" in Geochimica et Cosmochimica Acta, v. 166, p. 189-209. Table 1. δ18O and δ13C values for glassy and frosty foraminifera from TDP Site 18 and ODP Site 865, respectively. Table 2. Sr/Ca and B/Ca values, and test weights for glassy and frosty foraminifera from TDP Site 18 and ODP Site 865, respectively. Table 3. δ11B values for glassy and frosty foraminifera from TDP Site 18 and ODP Site 865, respectively.

Strontium/calcium, magnesium/calcium, lithium/calcium and boron/calcium ratios of 107 aragonite samples precipitated in vitro using a pH stat titrator using the constant composition technique between August 2020 and April 2022. Measured seawater pH and dissolved inorganic carbon concentrations (DIC) are used to estimate the seawater aragonite saturation state (O) of each precipitation. Aragonite precipitation rates are estimated from the rate of titrant dosing. The trace element contents of the solid produced in the experiment was corrected for the composition of the seed used as a surface for aragonite growth. Seawater [Sr], [Mg], [Li], [B] and [Ca] were also measured and seawater [B(OH)4-] is estimated from total seawater [B] and pH. Data were collected to determine how changes in the calcification fluids of calcareous organisms affect aragonite precipitation. Data were collected by Cristina Castillo Alvarez and Ed Hathorne and interpreted by Cristina Castillo Alvarez, Nicola Allison, Adrian Finch, Kirsty Penkman, Roland Kröger, Ed Hathorne and Matthieu Clog.