I can't read that at all.

(I have my own difficulties with vision).
Is it a quote from somewhere?
When something glows under uv, it's difficult to mistake the colour. It tends to be very bright.
Is there a chemist in your link stating that manganese might go orange?
I've certainly never, ever heard of that.
It's repsonsible for sun-purpling, or (as Christine says) purple coloured glass; it neutralises a nasty yellowy green that can appear if iron is present in clear glass, and glows a faint green under UV.
edited to add.
I found a link buried in your wonky text after much peering

and had a look.
I don't know who wrote it, or what authority or qualifications that they have, or what their level of knowledge is.
They do talk a lot about "vaseline" glass - that's a purely american term.
I suspect the writer of the blog is just mistaken about manganese glowing orange.