Section 184.1409 - Ground limestone(a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding, and classifying of naturally occurring limestone.(b) The ingredient meets the specifications of the Food Chemicals Codex, 3d Ed. (1981), p. 173, which is incorporated by reference. Copies are available from the National Academy Press, 2101 Constitution Ave. NW., Washington, DC 20418, or available for inspection at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html.(c) In accordance with § 184.1(b)(1) , the ingredient is used in food with no limitation other than current good manufacturing practice.(d) Prior sanctions for this ingredient different from the uses established in this section do not exist or have been waived.48 FR 52442, Nov. 18, 1983