[
 {
  "value": "4.4683e9",
  "sigma": "0.0024e9",
  "source": "Jaffey et al., Phys Rev C 4, 1889",
  "year": "1971",
  "field": "geology",
  "id": "Q09",
  "unit": "yr",
  "quantity": "U-238 half-life",
  "grade": "recalled standard value, PRIOR-ART row 20",
  "bound_low": "",
  "bound_high": "",
  "recalled": "yes"
 },
 {
  "value": "7.0381e8",
  "sigma": "0.0048e8",
  "source": "Jaffey et al., Phys Rev C 4, 1889",
  "year": "1971",
  "field": "geology",
  "id": "Q10",
  "unit": "yr",
  "quantity": "U-235 half-life",
  "grade": "recalled standard value, PRIOR-ART row 20",
  "bound_low": "",
  "bound_high": "",
  "recalled": "yes"
 },
 {
  "value": "1.248e9",
  "sigma": "0.003e9",
  "source": "Renne et al. / Min et al. K-40 total half-life",
  "year": "2011",
  "field": "geology",
  "id": "Q11",
  "unit": "yr",
  "quantity": "K-40 half-life",
  "grade": "recalled standard value, PRIOR-ART row 20",
  "bound_low": "",
  "bound_high": "",
  "recalled": "yes"
 },
 {
  "value": "4.961e10",
  "sigma": "0.016e10",
  "source": "Rotenberg et al., Geochim Cosmochim Acta 85, 41",
  "year": "2012",
  "field": "geology",
  "id": "Q12",
  "unit": "yr",
  "quantity": "Rb-87 half-life",
  "grade": "recalled standard value, PRIOR-ART row 20",
  "bound_low": "",
  "bound_high": "",
  "recalled": "yes"
 },
 {
  "value": "5700",
  "sigma": "30",
  "source": "NNDC / Kutschera, C-14 half-life",
  "year": "2013",
  "field": "geology",
  "id": "Q13",
  "unit": "yr",
  "quantity": "C-14 half-life",
  "grade": "recalled standard value, PRIOR-ART row 20",
  "bound_low": "",
  "bound_high": "",
  "recalled": "yes"
 }
]