Step 1: Open a New Sketch.
Then using a series of arc lines and splines i traced over the picture of the Celtic Knot.
After the sketch was complete i scaled the sketch down to roughly the size of a broach.
Step 2: Extrude.
I then inserted a plane on top of the part.
Then i drew two arced boxes to produce an extruded cut in order to give the part the curved appearance of a broach.
The final step was to extrude two mounting points for a fastening pin at the rear of the part.
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