This guitar was seen sitting on stage behind Kurt on a gig played on September 30, 1989, alongside a red Hagstrom. As opposed to the latter, which was used in November/December 1989, the Firebird was never actually played live.
Model?
Based on this single photo, the guitar is either an Ibanez Firebird copy or a Greco FB 900. Both of these guitars look exactly the same, so without actually seeing the logo on the headstock, it would be impossible to know. The color seems blue, but it could be that the light is playing a trick and that the guitar is actually black – which seems to be a much more common finish on these guitars.
Probably belonged to another band on the bill.
The only other band on the bill was Eleventh Dream Day and they never used guitars like that
neither did Kurt. Wonder who owned this
Besides it being a Ibanez/Greco Non-reverse Firebird it could also be a Vintage 1970s Aria Non-Reverse Firebird (as it looks exactly the same as the Ibanez Firebird Copy / Greco FB 900). Here’s an 1970s Aria Non-Reverse Firebird (this one is brown though but the body and everything is exactly the same as the other two models)…
Vintage Aria Non-Reverse Firebird w/hard case 1970’s Brown https://reverb.com/item/36921577-vintage-aria-non-reverse-firebird-w-hard-case-1970-s-brown?utm_source=android-app&utm_medium=android-share&utm_campaign=listing&utm_content=36921577