An 18ct gold diamond ring

An 18ct gold diamond ring,
a Swiss cut diamond, star set, to carved scrolling shoulders and a plain polished shank. Chester 1911, 3.33g.
Finger size O
Sold for £260

Condition report:
Minor surface marks/scratches to mount.
Slight wear to hallmark, hallmark still very clear.
Maker's mark S.U.Ltd, unidentifed.
Ring is hallmarked 18ct gold.
Diamond measures approximately 2.90mm, estimated as approximately 0.09ct.