“…The location of the JCC production center was located well outside the town, in vicinity to the F I G U R E 2 Geological map of the Jerusalem area (JCC = Jerusalem Convention Center; JQ = Jewish Quarter; F = formation) (after Sneh & Avni, 2011), showing also the Qidron, Refaim, and Soreq rivers (dashed lines); numbers denote approximate locations of soil samples [Color figure can be viewed at wileyonlinelibrary.com] TA B L E 1 Samples analyzed in this study according to type, class, and period Thus, a very limited amount of published archaeometric studies focusing on Jerusalem pottery production during the Iron Age (or any other period) is actually available. A "Jerusalem Reference Group" was defined in the literature (Mommsen et al, 1984) more than 30 years ago and has been quoted ever since (e.g., Gunneweg, Asaro, Michel, & Perlman, 1994;Gunneweg, Perlman, & Meshel, 1985, p. 283;Perlman, Gunneweg, & Yellin, 1986, It was therefore assumed in several publications that this Moz . a clay would represent by default the clay sources of ancient Jerusalem pottery, possibly due to its being a natural "clay" source.…”