Definition of "quartz-rock" []

• Quartzite. (noun)

The Century Dictionary (Public Domain)

• "Some poor miner usually finds a ledge of quartz-rock and digs down the way the ledge goes."
• "The other main line, namely, that of the Portillo, is of a totally different formation: it consists chiefly of grand bare pinnacles of a red potash-granite, which low down on the western flank are covered by a sandstone, converted by the former heat into a quartz-rock."
• "Where it occurs in veins of quartz-rock (the usual matrix), these veins are generally irregular in their thickness, often coming abruptly to an end as one follows them downward, and still more irregular and uncertain in the percentage of gold to rock."