\link{http://www.whatreallyworks.co.uk/start/articles.asp?article_ID=1123"What Really Works"} says:
"Spa water has a very low mineral content, with no more calcium or magnesium than soft tap water, but this low mineral content makes it good for people with kidney disease.
Volvic water also has a low mineral content.
The French water Badoit has one of the highest sodium contents of bottled mineral waters, and almost 25% of the RDA for calcium, and 28% of the RDA for magnesium. It is also very high in bicarbonate.
Perrier water is also high in bicarbonate, but the calcium content is only around 18% of the RDA.
San Pellegrino, the Italian mineral water, has less sodium than Badoit but 17% of the RDA for magnesium, and 23% of the RDA for calcium.
Evian provides a reasonable source of magnesium and calcium, and bicarbonate.
As a general rule, don’t give babies mineral and bottled waters, because the mineral content may not be appropriate for small babies’ kidneys, and also because they may not be bacteriologically safe – tap water that has been filtered, then boiled and cooled is still your best bet."
Seems fair enough.