Table 1 Criteria for characterization of fossil eggshell preservation.

EggshellLocalityMn
(ppm)
Fe (ppm)CL image %
luminescent
Preservation test*Final preservation
characterization
Low-trace
metals
% Lum.Microstructure1° Aragonite
Troodon formosus
(Theropod) TMP
2008.75.127
Devil’s Coulee,
AB, Canada
60760.5✓✓✓✓✓✓NAWell preserved
Maiasaura
peeblesorum
(Hadrosaur)
TMP 2009.153.1
Devil’s Coulee,
AB, Canada
156074111.3✓✓NAModerately preserved
Hypacrosaurus
stebingeri
(Hadrosaur)
TMP 1989.69.10
Devil’s Coulee,
AB, Canada
42912313NAXNANANAPoorly preserved
Troodon formosus
(Theropod) TMP
1995.21.4
Wann’s Hill,
AB, Canada
99540.6✓✓✓✓✓✓NAWell preserved
Indeterminate
lambeosaurine
(Hadrosaur) TMP
1988.121.41
Wann’s Hill,
AB, Canada
3265162373XXXNAPoorly preserved
Troodon formosus
(Theropod) TMP
2003.81.1
Lost River
Ranch, AB,
Canada
6280✓✓✓✓✓✓NAWell preserved
Magyarosaurus
dacus (Sauropod)
TMP 1991.175.2
Tuştea, Haţeg
Basin,
Romania
795615✓✓NAModerately preserved
Gastropod W20Wann’s Hill,
AB, Canada
79297NA✓✓NANA✓✓Well preserved
Bivalve TMP
2009.149.5
Milk River, AB,
Canada
21821NA✓✓NANA✓✓Well preserved

*If the sample passed, it received a “✓✓”; partially passed, a “✓”; or failed, a “X.” NA indicates that either test was “not applicable” (e.g., original biomineral was calcite) or “not available” (e.g., no thin sections available).

†Average of duplicates run to test stability of mass spectrometer.