Dude I just came back from the jewelers buying a new necklace for my girl’s birthday.
See if you like the idea of getting her some sort of bracelet, earrings, necklace, etc that has her birthstone in it (since you’re talking about this now I’m assuming her birthday is soon, in that case Ruby is the July birthstone just so you know). The one I got her is a gold chain with a pendant (or whatever its called) that has alternating rubies and diamonds in it.
The most important thing is to find something that you could envision her wearing. If shes a modest girl and the salesman is showing you a gawdy stone that costs a lot, don’t get that one just because you think she’ll be impressed by the price tag.
Just remember, most girls like jewelry. It usually causes them to swoon and take off their panties as if they’re on fire. If your girlfriend is in the other 1% of the population of girls that doesn’t like jewelry then I can’t help you out. In that case just buy her some more Test or D-bol - that’ll keep her happy.