Strange question as Monazite is a mineral.
If the question was, "which elements compose monazite", it could be possible to answer, Th, REE (Ce, Ln, Y.....) and P.
If he question was, " which mineral do we usually find together with monazite", it could be possibe to answer , Ilmenite, Rutile & Zircon
thorium
thorium
Ytterbium is found in minerals such as xenotime, euxenite, and monazite. It is also found in small quantities in some rare earth minerals and in the Earth's crust. Commercially, ytterbium is typically obtained through the process of ion exchange and solvent extraction from monazite sands.
Monazite sand is far more common than large monazite rocks and large beds of monazite don't exist. Not all monazite contains thorium.
Thorium is extracted from minerals as monazite, thorite, thorianite.
Some thorium minerals are: monazite, thorianite, thorite.
The common minerals of thorium are: monazite, thorianite, thorite.
Yttrium is found as an oxide in rare earth minerals such as monazite and bastnasite.
Important minerals of thorium are: monazite, thorite, thorianite, allanite.
Titanium,Zircon, Monazite, tin, iron ore,and salt
Some thorium minerals are: monazite, thorite, thorianite, allanite.
Important minerals of thorium are: monazite, thorite, thorianite, allanite.