
Neodymium is a component, of didymium glass: Crookes Glass (1926); this is a special glass for goggles used during glass blowing and welding.
Neodymium glass is used to make lasers: Neodymium glass laser having an output at about 9180 a [sic] (1966).
Neodymium oxide is used as an exhaust gas catalyst (Neodymium Oxide Catalyst Compositions (1969)), and as a catalyst for preparing esters (Neodymium Oxide As Catalyst For Preparing Esters (1964)).
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All patent information has been obtained from Espacenet (European Patent Office).