It does not take the. place of talking to your doctor or. pharmacist. The information in this leaflet was. last updated on the date listed on the. final page. More recent information. on the medicine may be available.
Yttrium never occurs in nature as a free element. It is found in almost all rare earth minerals and in uranium ores. The yellow-brown ore xenotime can contain as much as 50% yttrium phophate (YPO4) and is mined in Malaysia.
Thallium is found in the minerals crookesite TlCu 7 Se 4, hutchinsonite TlPbAs 5 S 9, and lorandite TlAsS 2. Thallium also occurs as a trace element in iron pyrite, and thallium is extracted as a by-product of roasting this mineral for the production of sulfuric acid.