Multiple choice general knowledge science & technology Monazite is an ore of titanium zirconium iron thorium Reveal answer Fill a bubble to check yourself D Correct answer Explanation Monazite is a phosphate mineral that is the primary commercial source of thorium, along with containing rare earth elements. It is not an ore of titanium (which comes from ilmenite/rutile), zirconium (zircon), or iron (hematite/magnetite).