Driftwood
You know that plenty of driftwood lies along the shore. Let us make several rafts, and carry them to a suitable place. If our plot succeeds, we can wait patiently for the chance of some passing ship which would rescue us from this fatal island.
— Andrew Lang, "The Seven Voyages of Sindbad the Sailor"
The Andrew Lang above was also co-author of a well-known translation of Homer's Odyssey. It would be nice if Lang had used the word "ebony", agreeing with Laurence Housman, another Arabian Nights translator who entitled another tale in his book "The Story of the King of the Ebony Isles". Instead Lang entitled the tale "The Story of the Young King of the Black Isles". This is to say that even pure speculation is fun here, while the quote above helps to know some "driftwood".
Another clue is perhaps found in a song by Roger Waters, which is apparently inspired by "Opel" and begins like this:
Sea shell and stone
Surf rushes forward to feel the shingle with fingers of foam
Search for the gold
Over the landscape the mouth of a lifeline unfolds
- — Roger Waters, "Sea Shell And Stone"
This song with such a "Syd-Homeric" title is supposedly about the body of a pregnant woman, but on his 1970 album Music From The Body you may hear the odd word that recall Opel (e.g. "glisten and glimmer and shimmer and sparkle and still" recalls an opal, and the line "Far, far away there is a field …" recalls the far distant shore).
Waters, Roger. "Sea Shell and Stone." Music from The Body. By Ron Geesin, and Roger Waters. EMI, 1970. LP. http://www.youtube.com/watch?v=zwjwP_hB-2A
