The 5yo homebred mare gave Bob and Sandra Peters their fourth win in the Perth Cup while creating history for apprentice Kyra Yuill who became the first female rider to capture the feature.
The Grant Williams trained mare took her overall record to 8 3 4 27 for earnings of $587,990.
Western Jewel finished fourth in the last Perth
Cup when it was run in January.
"We were very unlucky last year. We thought with a better run we should have won," Williams told Sky Racing World.
"This is her sort of race. We knew we had to ride her for one last sprint."
It was a dream come true for her young jockey.
"It's amazing, it's unreal. I'm just
lucky to have a good horse that can do it for me," Yuill said.
"I didn't really want to be on the fence but I ended up there and was able to pop off."
"It all worked out my way. I didn't really expect to be that wide but she got a good roll-on."
Western Jewel comes from the tenth and final crop sired by Shadwell's overachieving import Jeune who won the Hardwicke Stakes (G2) in England before winning four times at the highest level in Australia.
Western Jewel is the second foal of the 3-time winner Our Millster a daughter of Marooned out of the top-class mare Timeless action (Serheed) whose six wins included the Group 3 Strickland Stakes and was twice Group 1 placed.
Our Millster has a gelded 2yo by Hard Spun named Western Blaze, a yearling filly by Charge Forward and a colt foal by Hard Spun.