As the silicon crystal grows oxygen is incorporated as an interstitial atom in the silicon matrix at a concentration of typically 10-40 ppm.
Therefore the true concentration of the colloidal calcium carbonate is likely to have been 89 or 101 ppm as CaCO3.
Dalradian limestones commonly have Sr greater than 1000 ppm, indicating primary aragonite and marine diagenesis.
There was a clear dose related increase in parathyroid gland hyperplasia from the lowest dose 400 ppm.
The dolomite marbles have an average Sr content of 115 ppm.
