I couldn't fit it quite where Tolkien did, but it's over the s in "Westmarch." The letter a is represented by three dots over the r.
Before we can go on, we need to pause and understand how Tengwar works, because it's a little more complicated than Cirth runes.
Also, having to edit multiple glowing blades in every scene with Orcs would be costly and something easily sacrificed if there are time restraints. Conversely, it could just have been a mistake by Jackson and the team, as the glowing blades aren't mentioned much in the books and could be easily forgotten in editing. One reason for only making Sting glow could be because it makes Frodo's sword feel more unique and helps him stand out as the hero. RELATED: Lord of the Rings: How Andy Serkis' Performance Prompted an Iconic Gollum Redesign This very well may have been an intentional omission by director Peter Jackson, as otherwise, the lack of glowing is quite a big error. As Bilbo gives the sword to Frodo in Rivendell, he explains its properties but doesn't specifically say that it glows because it's Elvish. The Lord of the Rings trilogy tends to keep very close to the books, so taking away the swords' glowing properties definitely stands out. The novels describe each of the swords glowing blue when Orcs are nearby, yet in the movies, Sting is the only sword ever shown to do so, even when the other Elvish blades are cutting up Orcs.