Katy Perry and John Mayer on Feb. 14 with her ring (inset)
David Tonnessen/Pacific Coast News
02/17/2013 at 09:40 AM EST
put a ring on Katy Perry
's finger – just not the kind you might expect.
After the couple was photographed leaving Vincenti, an Italian restaurant in Los Angeles, on Valentine's Day, Perry was spotted wearing a ruby on her ring finger, leaving many to ask if Mayer, 35, had popped the question.
Although Perry, 28, is beaming in the photo, a source tells PEOPLE the couple is "not engaged."
While the one-of-a-kind ring was created by Daniel Gibbings
, a Santa Barbara based jeweler and designer, it may have nothing more than a Valentine's Day gift that a rep for Gibbings says the singer-songwriter selected himself.
Mayer was "really super nice" while shopping for his girlfriend, the rep adds.
But as for speculation over whether the heart-shaped ring could be seen as a possible engagement ring, the rep says that while it's not a traditional design, "it can be."
"[Gibbings] uses a lot of texture. The style of his engagement rings are not the usual Neil Lane looking ring. They are definitely more trendy or boho," the rep adds.
With reporting by JENNIFER GARCIA & JESSICA HERNDON