All the cities along the Mississippi River had been marked as contaminated to some extent.
Both the air and the water in their neighbourhood were contaminated thereby.
Galena (q.v.), the principal lead ore, has a world-wide distribution, and is always contaminated with silver sulphide, the proportion of noble metal varying from about o of or less to o 3%, and in rare cases coming up to 2 or i %.
When amongst the litter of a properly mated, highly bred fox-terrier, pups are found with long bodies and thick short legs and feet, breeders are disposed to excuse the result by the supposition that the bitch has been contaminated by some earlier mating.
Since all sulphuretted copper ores (and these are of the most economic importance) are invariably contaminated with arsenic and antimony, it is necessary to eliminate these impurities, as far as possible, at a very early stage.
