KISH GEOCHEMICAL STUDIES OF PUMICE 221 Table 6. Volcanic Rock Names for Florida Pumice Artifacts. Sample Location TAS Name! ___K - Alkalinity’ Southern Florida MDC 1.567.6b Miami Circle Rhyolite* High K MDC 1.66.4 Miami Circle Rhyolite High K MDC 1.222.1la Miami Circle Andesite Medium K MDC1.472.4 Miami Circle Rhyolite High K MDC 1.893.1 Miami Circle Rhyolite High K HMSF 896 Brickell Point Rhyolite High K FBAR 75.62.10.1 Higgs Site Rhyolite High K FBAR 72.20.534.1 Indian Key Rhyolite High K FLMNH A16262a Fort Center Rhyolite High K FLMNH 98576 Bear Lake | Rhyolite* Medium K HMSF 582.1 Brickell Point Rhyolite High K HMSF 1018.18 Granada Rhyolite Medium K HMSF29472.1 Honey Hill Rhyolite Medium K HMSF 427.5 Custom House Basalt Medium K FBAR 74.2.10.8 Stock Island Rhyolite High K FBAR 00.14.47.1 Deering Estate Rhyolite High K FBAR 76.209.1 Shark Butchery Rhyolite High K FBAR 99.65.7.1 Whitebelt 1 Rhyolite Medium K HMSF 1874.1B Sutton Site Andesite Medium K Northwestern Florida EGLIN 056 Wynnhaven Beach Andesite High K EGLIN 198 Wynnhaven Beach Basaltic Shoshonite Trachyandesite EGLIN 742 Wynnhaven Beach Rhyolite* High K 1 Classification of samples based upon TAS (total alkalies-silica) diagram of La Bas et al. (1986) 2 Potassium alkalinity classification based upon the diagram of Peccerillo and Taylor (1976) All High-K rhyolite samples are also classified as being “high-silica” except for the samples marked with an asterisk. It is present along most of the archeological sites on the Atlantic coastline of central and southern Florida, the adjacent Keys and inland near Lake Okeechobee. The limited number of analyzed, medium-K rhyolitic pumice samples appear to come from a restricted region of sites that are located a few kilometers north of the Miami Circle and at one site (Bear Lake 1) at Cape Sable on Florida Bay. Additional Major Element Characteristics Igneous rocks that have a granitic-rhyolitc composition fall within a narrow field when plotted on a triangular diagram of the normative minerals albite-quartz-orthoclase. Tuttle and Bowen (1958) found that for a large number of analyzed samples (1269) that were classified as either granites or rhyolites most of the samples had approximately equal propor- tions of the three normative minerals (Figure 7). Chemical