It would appear that I'm not the only one who'd like to know. Stockholm's Abba Museum dearly wanted the guitar as an exhibit, but it has mysteriously "gone missing" - under what circumstances we are not told - along with its twin, an identical guitar finished in gold.
Both guitars were created by the now legendary Swedish guitar manufacturer Hagström [NOTE: not true, see UPDATE #2 below], the gold one reportedly having been given as a prize for a competition held by German magazine Bravo. Björn only seemed to use the silver star guitar during the "Waterloo" period, at the 1974 Eurovision Song Contest itself in Brighton, and on subsequent TV appearances when performing "Waterloo". As far as I am aware, he didn't play it publicly after this or for promoting any of their other songs.
Not one of the news reports I found made any mention of the last known whereabouts of the guitar (or its twin), although there were one of two references of one (or both?) of the guitars possibly being in the collection of a German fan.
Unfortunately, I cannot find any decent photographs of either guitar, other than the blurry TV screenshots showing Björn playing the silver star guitar that I've reproduced above. [As an aside, I always thought it was more "explosion"-shaped, rather than star-shaped, but that's what everyone else calls it. "Star guitar" makes me think of the 5-pointed star guitar used by the Glitter Band.]
So, do you know what happened to this important artefact of pop music history? I, for one, would love to know.
UPDATE: The plot thickens! This is getting more confusing. Was the star guitar actually built by Hagström as reported elsewhere? I found another link last night (and can I find that page again?) linking to the guy who supposedly built the star guitar for Abba. Goran Malmberg's website, which mainly focusses on sports cars, mentions that he used to be a guitar builder and still builds guitars now and then for special customers, and also shows some pictures of Abba and the star guitar (in one close-up we can clearly see the Malmberg logo on the scratchplate) plus pictures of Malmberg building a new star guitar for the Abba museum.
UPDATE #2: The Star Guitar is NOT a Hagström! It's a Malmberg!
Through the wonder of email I've been in touch with Goran Malmberg who tells me that (in his own words):
I did build the star ABBA guitar. I heard rumors myself about that Hagstrom should have built the guitar, but that's not so. It might be becouse Hagstrom is one of the few known guitar fabricators in Sweden, people draws the conclusion that they must have been the builder then. I am in no way connected with Hagstrom.So, that's part of the mystery solved. The whereabouts of the original is still unknown, and what was all this talk of a second guitar finished in gold? Was there ever a gold star guitar? A copy perhaps by another builder? Hagström even? (Could this be where the confusion came in as to who built the original?)
I have been in contact with the ABBA museum (under build up in Stockholm) about the guitar, and the guitar is really missing. From what I understand ABBA liked to alter their performance including new instruments, and the got other things to do than storing old stage gear. So, these things were left to roadies to handle. Time is passing by, and when the old star guitar is asked for around the world these days, no one knows who took care of it and where the guitar are.
There was ONLY one guitar made. In silver flake. The paint was in fact a Hot Rod car flake on a silver base with 100 (or something) layers of varnish on top. Might look as any base colour in a spotlight.
I designed the entire guitar shape. The original question from Bjorn was that they liked a guitar in the shape of a star, and I made a few baseline drawings for him to look at. If you look at the shape it is not symmetrical. We have the Gibson guitar "Flying V" and "Explorer" from the time that has "horns" in different directions. A common thing with those guitars along with my star guitar is that it has to serve a practical purpose, therfore the horns are pointing logical directions. The strap has to be fastened in a good balance possition. There should be no horn where one has its right arm. There has to be a horn to place tone and volume knobs. So the design issue was to find a design balance that included those features. I have seen copies of the guitar. No criticism, but if the builder does not has a very good picture to make a copy from, he will surley miss the geometric figures behind the design. And the guitar will not show the same harmony as the original.
About the "player" issue, it is just about the same as a Strat with patent number pickups. The body is laminate plywood, for the reason that the edge of the horns should not break. It is all solid as a Strat. Good sustain. However, the guitar main purpose was for image, and even if Bjorn had som "asking" for it as an instrument, there was newer any time for fine tune adjustments.
I am right now making two more copies of the guitar, one that is for the ABBA museum, for Bjorn to "accept" as alike during opening. The other is probably sold to an Italian ABBA enusiast. I am putting every possible effort to make them as original as possible.
I'd like to thank Goran for taking the time to answer my questions. Remember, you read it here first, folks!
UPDATE #3: Yes, there was a Gold Star Guitar!
See: www.youtube.com/watch?v=mi_qKXA0GCA. This will be the one belonging to the German fan who supposedly won it in a magazine competition. This guitar would not have built by Goran Malmberg, and is a copy of the original.