Pink patina on brass RPF Costume and Prop Maker Community

Hey folks, I'm having a bit of a problem. I'm doing some brass etching, but the end product will always have this pink patina to it. I've tried sanding it, polishing it with steel wool and scrubbing it to kingdom come with brasso but to no avail. The picture I'm showing had all three done to it

REMOVING PINK COLOR FROM BRASS

Style 5526/5528/5529

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REMOVING PINK COLOR FROM BRASS

REMOVING PINK COLOR FROM BRASS

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