Quote Originally Posted by sblock View Post
... a lot of other makers have more-or-less adopted the convention of using the number "4" to designate a carved-top, oval-hole mandolin, and "5" to designate a carved-top mandolin with f-holes. Also, many also use the letter "F" to designate a body shape with points and scroll, and the letter "A" to designate a simpler. teardrop-shaped body without these features.

Thus, we get:

A4 oval hole, teardrop body (also, A2, A3, A2Z)
A5 f-holes, scroll and points
F4 oval hole, scroll and points
F5 f-holes, scroll and points
Methinks thou didst mispeak. Perchance 'twas "teardrop body" intended.

That said, the Gibson Florentine A-5 was introduced in 1957 with the two points mentioned below. But no scroll. I've always assumed the "F" designation was applied to mandolins with the distinctive shape that includes scroll on the bass side and points on the treble side. The A-5 having no scroll, even with points (albeit differently located), was thus given its model number. And yet ... in 1971 the A-5 changed to feature the infamous "lump scroll." I'm of the opinion the model was an anomaly, by and large. It was discontinued in 1979.

This and much, much more fun stuff are provided here. As I mentioned earlier, it's not complete nor up-to-date.

http://www.guitarhq.com/gibson8.html