As a symbol of hardness or fixedness of character

    silex icis, m and (poet.) f    a hard stone, flint, flint-stone, fire-stone, granite: silicem caedere: vias sternere silice, L.: silici scintillam excudere, V.: silicem iaculatus in hostīs, O.: silicem pedibus quae conteret atrum, Iu.: privos lapides silices secum ferre, L.— As a symbol of hardness or fixedness of character: non silice nati sumus: Nec rigidas silices in pectore gerit, O.—A rock, crag: Stabat acuta silex praecisis undique saxis, V.— Lime-stone: terrenā silices fornace soluti, O.