Native sulphate of strontia, found abundantly near Bristol, in the red marl formation.
Strontium obtained from carbonate of strontia by Sir Humphry Davy.
Lead salts must be absent in the titration, and so must strontia and lime.
strontia and baryta will flow into the charcoal, but lime will not.
The sulphate of strontia melts in the oxidation flame upon platinum foil, or upon charcoal, to a milk-white globule.
The color produced by the sulphate of strontia is less intense.
The insoluble salts of strontia do not produce a very intense color.
The carbonate of strontia swells up and produces a splendid white light, while the external flame is colored of a fine purple-red.
If the solution is turbid, traces of baryta or strontia may still be present and should be removed by filtration.
Baryta does not prevent the reaction of the soluble salts of strontia, unless it exists greatly in excess.