Hi,
Don't know that maker's mark, but do know that type of mark. The brooch is Native American inspired, but a mass produced cast piece of recent vintage. You'll notice the mark is on an oval raised plaque. These are produced in wax for the jewelry industry, the wax plaque is applied to the original wax casting model of the jewelry piece. This way each piece comes out of the mold pre-marked, no time wasted on the mark stamping process.
Regards, Tom
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