“This process does not require the three-step refinement needed to produce steel from ore.”

“The remnant ore inside the old stopes, pillars and tailings used as backfilling are being leached with mild acid solution.”

“The kind of ore that attracted iron was once called magnesian stone, because it was discovered in the part of Asia Minor near Magnesia.”

“It is extracted from its ores by heating lanthanum metal with ytterbium oxide.”

“It never occurs as a free element, but only in ores such as pyrolusite, manganite, psilomelane, and rhodochrosite.”

“Unlike aluminum, copper metal is fairly easy to obtain chemically from its ores.”