What's with Rau?

The desire sometimes comes upon me to take up verbification, and I will for some days employ myself in making up words. Yesterday was one of those days. (This is a good thing for my language, which would otherwise get very little attention right now.) Yesterday afternoon I was sitting outside with my thoughts on words and my eyes on a brilliant sunset when a very good word was presented to me: "rausta," which is a bright, fiery orange. If you have knowledge of Tolkien's languages you might recognize the similarity this word bears to some of his Quenya, and if you've followed this blog much you know that I enjoy his languages--the elvish ones in particular. Therefore I am always concerned that I may be subconciously copying him, so this word--"rausta"--I checked in my book of Tolkien's elvish etymologies. My word was not a direct copy, but I noticed some interesting similarities. Quenya has the word "rauta," which originally meant "copper" (though he later changed it to "metal"), and Sindarin has the word "raw," which is "lion". I also remembered another of my own words--"rautho," battle--and English words such as "row" and "rousing" that all seem similar. Rausta, rautho, rauta, raw, row, rousing; fiery orange, battle, copper, lion, row, rousing. They're all rousing, sometimes fierce, and seem to agree that a tawny copper/orange is the right color. The really surprising thing is that the agreement carries through several languages and not one but two verbificators. So I want to know, what's with rau?

Update: I've checked our Latin and Spanish dictionaries too. Latin "raudus" is "a peice of bronze" or "a copper coin" (hence perhaps Tolkien's original meaning for "rauta"?) and Spanish has "raudo" which means "rapid, impetuous".

Note on pronunciation: In my language, in Tolkien's, and in Latin and Spanish, "au" is pronounced like the "ow" in "now". (Thus "Sauron" is the "sour one". Yes, I know, sorry.) In Sindarin, "raw" would sound very much like English "row".