Origin of silica
Examples from the Web for silica
For the large number of abrasives produced from silica, outside of flint pebbles, domestic sources of production are ample.The Economic Aspect of Geology|C. K. Leith
On evaporating to dryness, and digesting in water, all the silica will remain in an insoluble state.A Dictionary of Arts, Manufactures and Mines|Andrew Ure
The most important determinations for these are total alkali and silica.The Handbook of Soap Manufacture|W. H. Simmons
Decomposition ensues, silica being deposited in a gelatinous state, and hydrofluosilicic acid remaining in solution.
Siliceous limestones, where their silica is original and of organic origin, have contained skeletons of sponges or radiolaria.