Opaline rhymes with:
polypropylene, polypropylene, acetylene, aniline, ethylene, evaleen, gasoline, magdalene, maybelline, mescaline, naphthalene, polyacetylene, polybutylene, polyethylene, polypropylene, tourmaline, valvoline, vaseline
Opaline sounds like:
o'fallon, o'flynn, ofallon, oflynn, opalina