{
 "title": "Geopolymers: masonry samples from Cusco (SEM-EDS)",
 "title_es": "Geopolímeros: muestras de la mampostería del Cusco (SEM-EDS)",
 "creator": "Trevor Hawke, Co-Director of Research, Pi Heritage Foundation",
 "publisher": "Pi Heritage Foundation",
 "source_page": "https://www.pirambla.org/geopolimeros.html#laboratorio",
 "reference": "Hawke, T. (2026). Evidence of geopolymer concrete in megalithic architecture of Cusco, Perú. Harmonic Research Group, April 2026.",
 "method": "Scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS); values in atomic percent. Cation saturation index = (Na+K+Ca+Mg)/Al. Rumiqolqa reference: mean K2O 2.31% over 124 samples (Ogburn et al.) converted to ~1.04 at%; chlorine as ultra-trace.",
 "method_es": "Microscopía electrónica de barrido con microanálisis (SEM-EDS); valores en porcentaje atómico. Índice de saturación catiónica = (Na+K+Ca+Mg)/Al. Referencia de Rumiqolqa: K2O medio 2,31 % en 124 muestras (Ogburn et al.), convertido a ~1,04 % atómico; cloro en traza.",
 "status": "measured; four samples, further authorized sampling pending",
 "status_es": "medido; cuatro muestras, pendiente de muestreo autorizado",
 "pending": [
  "Authorized sampling (Ministry of Culture of Peru)",
  "X-ray diffraction",
  "Thin-section petrography",
  "Independent laboratory",
  "Laboratory gamma spectrometry (HPGe)",
  "Carbon-14 dating of the micro-arthropod"
 ],
 "updated": "2026-10-10",
 "gamma_spectrometry": {
  "note": "In situ gamma spectrometry with a portable CsI(Tl) detector (Hawke 2026). Preliminary: the thorium/uranium ratio and the radon figure use the same 214Pb peak and must be confirmed together in the laboratory with an HPGe detector.",
  "note_es": "Espectrometría gamma in situ con un detector portátil de CsI(Tl) (Hawke 2026). Preliminar: la relación torio/uranio y la cifra de radón usan el mismo pico del 214Pb y deben confirmarse juntas en laboratorio con un detector HPGe.",
  "photopeaks": [
   "40K",
   "212Pb (238.6 keV, thorium series)",
   "214Pb (351.9 keV, uranium series)",
   "234Th (63.3 keV)"
  ],
  "data": [
   {
    "site": "Koricancha, Cusco",
    "th_u_ratio": 2.89,
    "radon_emanation_pct": 98.7
   },
   {
    "site": "Palace of Inca Roca, Cusco",
    "th_u_ratio": 2.88,
    "radon_emanation_pct": 95.7
   },
   {
    "site": "Rumiqolqa quarry (reference)",
    "th_u_ratio": 3.83,
    "radon_emanation_pct": ""
   },
   {
    "site": "Dense rock (typical reference)",
    "th_u_ratio": "",
    "radon_emanation_pct": "5-15"
   }
  ]
 },
 "version": "1.0",
 "date": "2026-09-30",
 "license": "CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/)",
 "columns": [
  "sample",
  "site",
  "si_al",
  "cation_saturation_index",
  "ca_si",
  "na_at_pct",
  "k_at_pct",
  "cl_at_pct",
  "mg_at_pct"
 ],
 "data": [
  {
   "sample": "1A",
   "site": "Koricancha, Cusco",
   "si_al": 2.48,
   "cation_saturation_index": 0.88,
   "ca_si": 0.12,
   "na_at_pct": 1.49,
   "k_at_pct": 2.18,
   "cl_at_pct": 0.52,
   "mg_at_pct": ""
  },
  {
   "sample": "1B",
   "site": "Koricancha, Cusco",
   "si_al": 3.12,
   "cation_saturation_index": 1.0,
   "ca_si": 0.12,
   "na_at_pct": "",
   "k_at_pct": 1.68,
   "cl_at_pct": 0.71,
   "mg_at_pct": ""
  },
  {
   "sample": "2A",
   "site": "Huaca Sapantiana, Cusco",
   "si_al": 2.17,
   "cation_saturation_index": 0.98,
   "ca_si": "0.12-0.13",
   "na_at_pct": "",
   "k_at_pct": "",
   "cl_at_pct": "",
   "mg_at_pct": ""
  },
  {
   "sample": "2B",
   "site": "Huaca Sapantiana, Cusco",
   "si_al": 2.42,
   "cation_saturation_index": 1.22,
   "ca_si": 0.12,
   "na_at_pct": "",
   "k_at_pct": "",
   "cl_at_pct": "",
   "mg_at_pct": 2.91
  },
  {
   "sample": "Rumiqolqa andesite (reference)",
   "site": "Rumiqolqa quarry",
   "si_al": "",
   "cation_saturation_index": "",
   "ca_si": "",
   "na_at_pct": "",
   "k_at_pct": 1.04,
   "cl_at_pct": "<0.01",
   "mg_at_pct": ""
  }
 ]
}