Even for ordinary window glass, sand must be +98% pure silica.

Intrinsic defects are present in the matrix of a single component glass material like pure silica.

The sand in the southern part of this village contains high concentration of pure silica.

The sand consists of 98% pure silica which gives it a bright white color.

The walls are almost pure silica, built up in layers half a meter thick.

It was almost, but not quite, pure silica and iron with some traces of elemental carbon.

The white to tan sands of the dune fields are almost pure silica.

The beach sand of Lake McKenzie is nearly pure silica.

Indeed as pure silica it is the insulating element in the technology of silicon microchips.

A large deposit of nearly pure silica in the town may prove of much value for glass and other ware.