Supplementary file S1: Chemical groundwater data used for analysis in the Journal article entitled "Li and Ca enrichment in the Bristol Dry Lake brine compared to brines from Cadiz and Danby Dry Lakes, Barstow-Bristol Trough, California, USA" by Michael R. Rosen, Lisa L. Stillings, Tyler Kane, Kate Campbell-Hay, and Matthew Vitale, P.G., Ray Spanjers, P.G.in the Journal Minerals Supplementary file S2: Chemical data from extractions from 10 clay samples from Bristol Dry lake by acid digestion. used in "Li and Ca enrichment in the Bristol Dry Lake brine compared to brines from Cadiz and Danby Dry Lakes, Barstow-Bristol Trough, California, USA" by Michael R. Rosen, Lisa L. Stillings, Tyler Kane, Kate Campbell-Hay, and Matthew Vitale, P.G., Ray Spanjers, P.G.in the Journal Minerals. Methods for all data are in the journal article. Data is for Bristol, Cadiz and Danby playas (Dry Lakes). Most data has been previously published either online in the California Division of Water Resources website, or in other USGS publications or journal articles. Some data from Cadiz Dry lake has not been previously published and publication of these data has been granted by Tetra Technologies Inc. and Standard Lithium LLC.