Elfarylfri (rhenium)

The construction "ylfri" for W (tungsten, wolfram) is a combination of "ylfi", a neuter noun derived from "úlfur" (a translation of the first part of "Wolfram") with addition of the first "r" in the second member "-ram", which makes the word sound like the dative of "silfur", silfri.  "Ylfi" on its own doesn't sound like the name of a metallic element. Addition of the "r" in "ram" does: ylfri

Rhenium was named after the river Rhine and is positioned right next to tungsten (wolfram): Elfar-ylfri, a funny rhyme word.  I like it.

So we have three words for rhenium

1) torsuðumálmur (highest boiling point)

2) elfarylfri (the "wolfram" (tungsten) named after a river (Rhine))

3) eðalþungsteinn (noble tungsten. Rhenium is a noble metal)