Assertion: lens's surface | /r/CapableOf | offer more protection
Facets:
value: from sparks
type: TRANSITIVE-OBJECT
value: from shards of material
type: OTHER
Source sentences:
text: They still remain in use for specialised circumstances, for example in extremely high prescriptions (currently, glass lenses can be manufactured up to a refractive index of 1.9) and in certain occupations where the hard surface of glass offers more protection from sparks or shards of material.